SLDS185D March   2012  – June 2016 PGA450-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings: AEC Q100
    3. 6.3  ESD Ratings: IEC61000-4-2
    4. 6.4  Recommended Operating Conditions
    5. 6.5  Thermal Information
    6. 6.6  Electrical Characteristics
    7. 6.7  Electrical Characteristics — LIN 2.1 Slave and Buffered SCI
    8. 6.8  Electrical Characteristics — SPI Interface
    9. 6.9  Timing Requirements
    10. 6.10 Timing Requirements — LIN 2.1 Slave and Buffered SCI
    11. 6.11 Timing Requirements — SPI Interface
    12. 6.12 Switching Characteristics
    13. 6.13 Digital Datapath Filter Switching Characteristics
    14. 6.14 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Power Supply Block
      2. 7.3.2  VREG
      3. 7.3.3  Clock
        1. 7.3.3.1 Clock Synchronizer Using the SYNC Field in the LIN Bus
      4. 7.3.4  Low-Side Drive FETs
      5. 7.3.5  Burst Generator
      6. 7.3.6  Low-Noise Amplifier
      7. 7.3.7  Analog-to-Digital Converter
      8. 7.3.8  Digital Data Path
        1. 7.3.8.1 Bandpass Filter (BPF)
        2. 7.3.8.2 Rectifier
        3. 7.3.8.3 Peak Extractor
        4. 7.3.8.4 Downsample
        5. 7.3.8.5 Low-Pass Filter
        6. 7.3.8.6 Datapath Output Format Control
        7. 7.3.8.7 Datapath Activation and Blanking Timer
        8. 7.3.8.8 Digital Datapath Output Mode
      9. 7.3.9  Transducer Saturation Time
      10. 7.3.10 Temperature Sensor
      11. 7.3.11 Free-Running Timer
      12. 7.3.12 GPIOs
      13. 7.3.13 8051W UART
      14. 7.3.14 8051 WARP Core
      15. 7.3.15 Memory
        1. 7.3.15.1 FIFO Memory for Digital Datapath Output
        2. 7.3.15.2 OTP Memory for Program
          1. 7.3.15.2.1 OTP Security
          2. 7.3.15.2.2 OTP Programming
        3. 7.3.15.3 EEPROM Memory for Data
          1. 7.3.15.3.1 EEPROM Memory Organization
            1. 7.3.15.3.1.1 EEPROM Cache
            2. 7.3.15.3.1.2 EEPROM Memory Cells
          2. 7.3.15.3.2 Programming EEPROM Through the 8051W and SPI
          3. 7.3.15.3.3 Reloading From EEPROM Cells Through the 8051W and SPI
      16. 7.3.16 LIN 2.1 Slave and Buffered SCI
        1. 7.3.16.1 Physical Layer
        2. 7.3.16.2 LIN Slave Mode
          1. 7.3.16.2.1 LIN Frame
          2. 7.3.16.2.2 LIN Registers
          3. 7.3.16.2.3 LIN Interrupts
          4. 7.3.16.2.4 LIN Slave Configuration
            1. 7.3.16.2.4.1 LIN Frame-Control Configuration
            2. 7.3.16.2.4.2 LIN Timing-Control Configuration
          5. 7.3.16.2.5 LIN Slave-Protocol State Machine
          6. 7.3.16.2.6 LIN Slave Protocol Rx
          7. 7.3.16.2.7 LIN Slave Protocol Tx
          8. 7.3.16.2.8 LIN Slave Status
            1. 7.3.16.2.8.1 LIN Slave Framing Error Status
            2. 7.3.16.2.8.2 LIN Slave Timing Error Status
        3. 7.3.16.3 SCI Buffered Mode
          1. 7.3.16.3.1 SCI Buffered-Mode State Machine
          2. 7.3.16.3.2 SCI Buffered-Mode Rx
          3. 7.3.16.3.3 SCI Buffered-Mode Tx
        4. 7.3.16.4 Connection of LIN Pin to 8051W
    4. 7.4 Device Functional Modes
      1. 7.4.1 Active Mode
      2. 7.4.2 Quiet Mode
      3. 7.4.3 RESET
    5. 7.5 Programming
      1. 7.5.1 SPI Interface
        1. 7.5.1.1 SPI Interface Protocol
        2. 7.5.1.2 Transfer Width
        3. 7.5.1.3 CheckByte
        4. 7.5.1.4 Examples
      2. 7.5.2 Diagnostics
        1. 7.5.2.1 Power-Block Monitors
        2. 7.5.2.2 Low-Side Diagnostics
        3. 7.5.2.3 Main Oscillator Watchdog
        4. 7.5.2.4 Software Watchdog
        5. 7.5.2.5 Internal ASIC TRIM Validity
        6. 7.5.2.6 FIFO RAM and External SRAM MBIST
        7. 7.5.2.7 Thermal Shutdown
      3. 7.5.3 8051W Interrupts
        1. 7.5.3.1 Interrupt Flag Clear
        2. 7.5.3.2 Priority Levels and Interrupt Vectors
        3. 7.5.3.3 Interrupt Latency
      4. 7.5.4 Instructions
        1. 7.5.4.1 Addressing Modes
          1. 7.5.4.1.1 Direct Addressing
          2. 7.5.4.1.2 Indirect Addressing
          3. 7.5.4.1.3 Register Addressing
          4. 7.5.4.1.4 Register Specific Addressing
          5. 7.5.4.1.5 Immediate Data
          6. 7.5.4.1.6 Indexed Addressing
        2. 7.5.4.2 Arithmetic Instructions
        3. 7.5.4.3 Logical Instructions
        4. 7.5.4.4 Data Transfers
          1. 7.5.4.4.1 Internal Data Memory
          2. 7.5.4.4.2 External Data Memory
        5. 7.5.4.5 Jump Instructions
          1. 7.5.4.5.1 Unconditional Jumps
          2. 7.5.4.5.2 Subroutine Calls and Returns
          3. 7.5.4.5.3 Conditional Jumps
        6. 7.5.4.6 Boolean Instructions
        7. 7.5.4.7 Flags
        8. 7.5.4.8 Instruction Table
      5. 7.5.5 8051W Port Usage
    6. 7.6 Register Maps
      1. 7.6.1 SFR Registers
        1. 7.6.1.1  I/O Ports (P0, P1, P2, P3) Registers
          1. 7.6.1.1.1 I/O Port 3 Register (offset = 0xB0) [reset = 0xFF]
          2. 7.6.1.1.2 I/O Port 2 Register (offset = 0xA0) [reset = 0xFF]
          3. 7.6.1.1.3 I/O Port 1 Register (offset = 0x90) [reset = 0xFF]
          4. 7.6.1.1.4 I/O Port 0 (P0) (offset = 0x80) [reset = 0xFF]
        2. 7.6.1.2  Stack Pointer Register (offset = 0x81) [reset = 0]
        3. 7.6.1.3  Data Pointer Registers
          1. 7.6.1.3.1 Data Pointer Register (offset = 0x82) [reset = 0]
          2. 7.6.1.3.2 Data Pointer Register (offset = 0x83) [reset = 0]
        4. 7.6.1.4  Power Control Register (offset = 0x87) [reset = 0]
        5. 7.6.1.5  Timer and Counter Control Register (offset = 0x88) [reset = 0]
        6. 7.6.1.6  Timer and Counter Mode Register (offset = 0x89) [reset = 0]
        7. 7.6.1.7  Timer and Counter Data Registers (TL0, TL1, TH0, TH1)
          1. 7.6.1.7.1 TL0 Register (offset = 0x8A) [reset = 0]
          2. 7.6.1.7.2 TL1 Register (offset = 0x8B) [reset = 0]
          3. 7.6.1.7.3 TH0 Register (offset = 0x8C) [reset = 0]
          4. 7.6.1.7.4 TH1 Register (offset = 0x8D) [reset = 0]
        8. 7.6.1.8  UART Control Register (offset = 0x98) [reset = 0]
        9. 7.6.1.9  UART Data Register (offset = 0x99) [reset = 0]
        10. 7.6.1.10 Interrupt Enable Register 0 (offset = 0xA8) [reset = 0]
        11. 7.6.1.11 Interrupt Enable Register 1 (offset = 0xE8) [reset = 0]
        12. 7.6.1.12 Interrupt Priority Register 0 (offset = 0xB8) [reset = 0]
        13. 7.6.1.13 Interrupt Priority Register 1 (offset = 0xF8) [reset = 0]
        14. 7.6.1.14 Program Status Word Register (offset = 0xD0) [reset = 0]
        15. 7.6.1.15 Accumulator Register (offset = 0xE0) [reset = 0]
        16. 7.6.1.16 B Register (offset = 0xF0) [reset = 0]
      2. 7.6.2 ESFR Registers
        1. 7.6.2.1  Bandpass Filter Coefficient B1 (BPF_B1) Register
          1. 7.6.2.1.1 Bandpass Filter B1 MSB Register (offset = 0x92) [reset = 0]
          2. 7.6.2.1.2 Bandpass Filter B1 LSB Register (offset = 0x93) [reset = 0]
        2. 7.6.2.2  Bandpass Filter Coefficient A2 (BPF_A2) Registers
          1. 7.6.2.2.1 Bandpass Filter Coefficient A2 MSB Register (offset = 0x94) [reset = 0]
          2. 7.6.2.2.2 Bandpass Filter Coefficient A2 LSB Register (offset = 0x95) [reset = 0]
        3. 7.6.2.3  Band-Pass Filter Coefficient A3 (BPF_A3) Register
          1. 7.6.2.3.1 Band-Pass Filter Coefficient A3 MSB Register (offset = 0x96) [reset = 0]
          2. 7.6.2.3.2 Band-Pass Filter Coefficient A3 LSB Register (offset = 0x97) [reset = 0]
        4. 7.6.2.4  Low-Pass Filter Coefficient B1 (LPF_B1) Registers
          1. 7.6.2.4.1 Low-Pass Filter Coefficient B1 MSB Register (offset = 0xA1) [reset = 0]
          2. 7.6.2.4.2 Low-Pass Filter Coefficient B1 LSB Register (offset = 0xA2) [reset = 0]
        5. 7.6.2.5  Low-Pass Filter Coefficient A2 (LPF_A2) Registers
          1. 7.6.2.5.1 Low-Pass Filter Coefficient A2 MSB Register (offset = 0xA3) [reset = 0]
          2. 7.6.2.5.2 Low-Pass Filter Coefficient A2 LSB Register (offset = 0xA4) [reset = 0]
        6. 7.6.2.6  Downsample Register (offset = 0xA5) [reset = 0]
        7. 7.6.2.7  BURST ON A Duration (ON_A) Registers
          1. 7.6.2.7.1 BURST ON A Duration MSB Register (offset = 0xA6) [reset = 0]
          2. 7.6.2.7.2 BURST ON A Duration LSB Register (offset = 0xA7) [reset = 0]
        8. 7.6.2.8  BURST OFFA Duration (OFF_A) Register
          1. 7.6.2.8.1 BURST OFFA Duration MSB Register (offset = 0xA9) [reset = 0]
          2. 7.6.2.8.2 BURST OFFA Duration LSB Register (offset = 0xAA) [reset = 0]
        9. 7.6.2.9  BURST ON B Duration (ON_B) Registers
          1. 7.6.2.9.1 BURST ON B Duration MSB Register (offset = 0xAB) [reset = 0]
          2. 7.6.2.9.2 BURST ON B Duration LSB Register (offset = 0xAC) [reset = 0]
        10. 7.6.2.10 BURST OFF B Duration (OFF_B) Register
          1. 7.6.2.10.1 BURST OFF B Duration MSB Register (offset = 0xAD) [reset = 0]
          2. 7.6.2.10.2 BURST OFF B Duration LSB Register (offset = 0xAE) [reset = 0]
        11. 7.6.2.11 Pulse Count A Register (offset = 0xAF) [reset = 0]
        12. 7.6.2.12 Pulse Count B Register (offset = 0xB1) [reset = 0]
        13. 7.6.2.13 Deadtime Register (offset = 0xB2) [reset = 0]
        14. 7.6.2.14 Burst Mode Register (offset = 0xB3) [reset = 0]
        15. 7.6.2.15 Temperature Sensor Register (offset = 0xB4) [reset = 0]
        16. 7.6.2.16 Saturation Deglitch Time Register (offset = 0xB5) [reset = 0]
        17. 7.6.2.17 Saturation Time Capture Register (offset = 0xB6) [reset = 0]
        18. 7.6.2.18 Control 1 Register (offset = 0xB7) [reset = 0]
        19. 7.6.2.19 Blanking Timer Register (offset = 0xB9) [reset = 0]
        20. 7.6.2.20 Free Running Timer (FRT) Registers
          1. 7.6.2.20.1 Free Running Timer MSB Registers (offset = 0xBA) [reset = 0]
          2. 7.6.2.20.2 Free Running Timer LSB Registers (offset = 0xBB) [reset = 0]
        21. 7.6.2.21 GPIO Control Register (offset = 0xBC) [reset = 0]
        22. 7.6.2.22 Clock Select Register (offset = 0xBD) [reset = 0]
        23. 7.6.2.23 Watchdog Enable Register (offset = 0xBE) [reset = 0]
        24. 7.6.2.24 LIN/SCI Select Register (offset = 0xBF) [reset = 0]
        25. 7.6.2.25 EEPROM Control Register (offset = 0xC0) [reset = 0]
        26. 7.6.2.26 Status 1 (STATUS1) Register (offset = 0xC1) [reset = 0]
        27. 7.6.2.27 Status 2 Register (offset = 0xC2) [reset = 0]
        28. 7.6.2.28 Power Mode Register (offset = 0xC3) [reset = 0]
        29. 7.6.2.29 Datapath and SCI Control Register (offset = 0xC4) [reset = 0]
        30. 7.6.2.30 FIFO Control Register (offset = 0xC5) [reset = ]
        31. 7.6.2.31 Enable Control Register (offset = 0xC8) [reset = 0]
        32. 7.6.2.32 LIN/SCI Rx Data (RX_DATAx) Register (offset = 0xC9 to 0xD1) [reset = 0]
        33. 7.6.2.33 LIN PID Register (offset = 0xD2) [reset = 0]
        34. 7.6.2.34 LIN/SCI Tx Data Registers (offset = 0xD3 to 0xDA) [reset = 0]
        35. 7.6.2.35 LIN/SCI Data Count Register (offset = 0xDB) [reset = 0]
        36. 7.6.2.36 LIN Configuration Register (offset = 0xDC) [reset = 0x40]
        37. 7.6.2.37 LIN Control Register (offset = 0xDD) [reset = 0]
        38. 7.6.2.38 LIN STATUS Register (offset = 0xDE) [reset = 0]
        39. 7.6.2.39 FIFO Pointer (FIFO_POINTER) Registers
          1. 7.6.2.39.1 FIFO Pointer MSB Register (offset = 0xDF) [reset = 0]
          2. 7.6.2.39.2 FIFO Pointer LSB Register (offset = 0xE1) [reset = 0]
        40. 7.6.2.40 VREG Select Register (offset = 0xE2) [reset = 0]
        41. 7.6.2.41 Sync Count (SYNC_COUNT) Registers
          1. 7.6.2.41.1 Sync Count MSB Register (offset = 0xE3) [reset = 0]
          2. 7.6.2.41.2 Sync Count LSB Register (offset = 0xE4) [reset = 0]
        42. 7.6.2.42 TEMP/DAC Control Register (offset = 0xE5) [reset = 0]
        43. 7.6.2.43 Oscillator Sync Control Register (offset = 0xE6) [reset = 0]
      3. 7.6.3 TEST Registers
        1. 7.6.3.1 ANALOG Test MUX Register (offset = 0xE9) [reset = 0]
        2. 7.6.3.2 DIGITAL Test MUX Register (offset = 0xEA) [reset = 0]
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Parameters
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Hardware
        2. 8.2.2.2 Firmware
          1. 8.2.2.2.1 Band-pass Filter Coefficients
          2. 8.2.2.2.2 Downsample Rate
          3. 8.2.2.2.3 Low-Pass Filter Coefficients
          4. 8.2.2.2.4 Pulse Count
          5. 8.2.2.2.5 Blanking Timer
          6. 8.2.2.2.6 FIFO Mode
        3. 8.2.2.3 OUT_A and OUT_B On and Off Times
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Community Resource
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7 Detailed Description

7.1 Overview

The PGA450-Q1 integrates power management, low-side drivers, analog front-end, digital datapath, and interface functions to form a full ultrasonic-sensor signal conditioning solution. The low-side drivers are programmed to drive a specific frequency that matches the external ultrasonic transducer. After transmitting, the same transducer receives the reflected echo signal. The analog front-end filters and amplifies this signal before storing the data in memory. The integrated 8051 microcontroller then processes this data to extract the useful information which typically includes how far away an object is from the transducer. At this point in the process, the information is transmitted through LIN, SCI, or UART.

7.2 Functional Block Diagram

PGA450-Q1 fbd_lds185.gif

7.3 Feature Description

7.3.1 Power Supply Block

The PGA450-Q1 uses three internal regulators (AVDD, DVDD, and VREF) as supplies for all of the internal circuits. The power-supply block also generates a precision voltage reference, current bias, and internal clock. The internal power-on-reset (POR) signal is released when the internal power supplies, voltage reference, current bias, and internal clock come into regulation.

Figure 7 shows the relationships of the power supplies and the POR signal in the PGA450-Q1 device.

PGA450-Q1 pwr_block_lds185.gif Figure 7. Power-Supply Block

The PGA450-Q1 begins to power up when a voltage is applied to the VPWR pin. Figure 8 shows a typical power-up diagram. The power-up time is typically about 3 ms.

PGA450-Q1 powerup_wf_lds185.gif
1. The VPWR ramp reaches POR level.
2. The internal reset to the digital core is released and EXTERNAL RAM MBIST is initiated. SPI communication is available.
3. 8051W reset is deasserted. Software starts execution.
4. EXTERNAL RAM MBIST is complete. External Scratchpad RAM and FIFO RAM available for use.
Figure 8. Power-Up Waveforms

The PGA450-Q1 provides two power-control bits for enabling different analog blocks to manage the total current consumption of the device. On power up, the device is in the QUIET mode with only the 8051W and LIN transceiver turned on. All other analog blocks are disabled. Setting the ACTIVE_EN bit enables the low-side drivers required for bursting as well as the echo-processing circuitry that includes the LNA and the ADC. In addition, a separate control bit, VREG_EN, is provided to enable the VREG circuitry, which is used to charge the external capacitor used during bursting.

The AVDD pin can be used to source current for up to 5 mA for resistive loads, including the loads on the GPIO and Tx pins.

Table 1. Power Modes

CONTROL BIT DEFAULT FUNCTION
1 VREG_EN Disabled Enables the VREG circuitry that provides the 100-mA current to charge the external capacitor used during bursting
2 ACTIVE_EN(1) Disabled Enables the LNA, ADC, ADC REF, and other support circuitry related to burst generation and echo processing
(1) ACTIVE_EN bit must be set before enabling the burst / saturation or echo-enable bits.

7.3.2 VREG

The PGA450-Q1 provides a regulated voltage output which, along with an external capacitor, can be used to drive the primary of the transformer used to excite the transducer. The VREG regulator provides a 100-mA current, sourced from VPWR, to charge the external capacitor. The user can select the desired VREG voltage by setting the VREG_SEL register to the appropriate value.

For VREG to be regulated to the selected voltage, VPWR must be at least 2 V above the selected VREG voltage.

The energy required for the burst comes from the external capacitor. The device has a VREG_READY status bit in the STATUS2 register to indicate when the capacitor is fully charged and has reached the regulation voltage.

PGA450-Q1 VREG_reg_lds185.gif Figure 9. VREG Regulator

This block is disabled by default. Setting the VREG_EN bit in the PWR_MODE register to high, enables this regulator.

7.3.3 Clock

The clock block generates the system clock that is used in the generation of burst, communication, echo time measurement, and the microprocessor clock. Figure 10 shows the clock block in the PGA450-Q1.

PGA450-Q1 clk_blk_lds185.gif Figure 10. Clock Block in PGA450-Q1

The CLK signal provided to various blocks inside the device is derived from one of the following sources:

  1. Internal oscillator without synchronization with communication: in this mode, the internal oscillator output is the source for the system clock.
  2. Internal oscillator with synchronization with communication: in this mode, the internal oscillator output is corrected for inaccuracy using time measurements of the communication bus. This mode requires the implementation of CLOCK SYNCHRONIZER logic in the digital control block. The clock synchronizer uses the SYNC FIELD to measure the timer value and adjust the internal oscillator output.
  3. External crystal: in this mode, a 16-MHz external crystal is the source of the system clock.

The clock source is controlled by the CLK_SEL register. Table 2 lists the settings of the CLK_SEL bits and the corresponding clock mode.

Table 2. Clock Selection

CLK_SEL BIT VALUES CLOCK SOURCE
0b00 Internal clock. Ignore the synchronization pulse received on the LIN bus.
0b01 Internal clock. Process the synchronization pulse received on the LIN bus.
0b10 External crystal clock
0b11 Internal clock. Ignore the synchronization pulse received on the LIN bus.

7.3.3.1 Clock Synchronizer Using the SYNC Field in the LIN Bus

The clock synchronizer block adjusts the internal oscillator based on a SYNC field in the LIN frame received in the communication line. The internal clock is trimmed to 16 MHz with ±4% tolerance in the TI factory.

The clock synchronizer improves the instantaneous accuracy of the internal oscillator frequency to 16 MHz ±0.5% using the LIN SYNC field, assuming an ideal LIN baud rate of 19.2 kBPS. The synchronization algorithm uses the time between two falling edges of the LIN SYNC field to adjust the internal oscillator.

The SYNC_COUNT is available for the 8051W to determine the effectiveness of the synchronization process based on the LIN SYNC field. That is, if the synchronization was effective, then the SYNC COUNT value should be close to 1667 ±8 counts.

This OSC SYNC value can also be updated by the 8051W microprocessor by setting the OVR bit in OSC_SYNC_CTRL ESFR.

PGA450-Q1 clk_synk_lds185.gif Figure 11. PGA450-Q1 Internal Clock Synchronization Control

Table 3 lists the value of OS<5:0> and the resulting change in frequency.

Table 3. OS<5:0> versus Delta System Clock Frequency

OS<5:0> Delta Frequency
0 –3.84 MHz
.. ..
31 –120 kHz
32 0 kHz
33 120 kHz
.. ..
63 3.72 MHz

NOTE

The clock synchronization feature is not available if the device is configured in SCI buffered mode. See the LIN 2.1 Slave and Buffered SCI section for details.

7.3.4 Low-Side Drive FETs

The PGA450-Q1 provides two low-side drivers for driving the primary of a transformer or an equivalent load. The Burst Generator section describes the control and drive modes for the low-side drive.

The low-driver block also has diagnostics. See the Diagnostics section for a description of the diagnostics.

Figure 12 shows the schematic of the low-side drive

PGA450-Q1 LS_drv_sch_lds185.gif Figure 12. Low-Side Drive Block Diagram

7.3.5 Burst Generator

The burst generator block generates the high-frequency pulses used to drive the gates of the low-side FETs. The low-side FETs ultimately drive the transducer by modulating the primary of the transformer.

The PGA450-Q1 provides mode bits in the BURST MODE register (see the Burst Mode Register (offset = 0xB3) [reset = 0] section) to configure each low-side drive MOSFET in three possible drive modes.

The three possible drive modes are:

    Single-ended:In this mode, one low-side switch is used to turn current on and off in the primary of the transformer. The rate of change of current in the primary generates a voltage in the secondary of the transformer, which is connected to the transducer.
    Push-pull:In this mode, two low-side switches are used to turn current on and off in two primary coils in the transformer. The primary coils have the same number of turns. The rate of change of current in the primary generates a voltage in the secondary of the transformer, which is connected to the transducer. The direction of current in the primary coils generates voltages of opposite polarity in the secondary, effectively doubling the peak-to-peak voltage in the secondary.
    8051W port drive:In this mode, the low-side switches are controlled through the an 8051W port pin.

Figure 13 shows the block diagram of the burst generator. The figure shows that the burst generator has a number of registers which the user software must configure.

PGA450-Q1 burst_gen_lds185.gif Figure 13. Burst Generator

The PGA450-Q1 provides 3 mode bits in the BURST MODE register to select from the five burst configurations available. Table 4 lists the modes of operation of the two low-side gate drives of the burst generator. For an understanding of the configurations, see Figure 14 and for an understanding of the waveforms, see Figure 15.

Table 4. Low-Side MOSFET Gate Drive Modes

ITEM DESCRIPTION
Mode Bits in BURST_MODE Register: 000
Mode description Low-side A and B are in push-pull
Low-side A trigger Write 1 to BURST_A_EN bit in EN_CTRL register
Low-side B trigger Write 1 to BURST_A_EN bit in EN_CTRL register
No. of pulses on A Set by PULSE_CNTA (0–63 pulses) register
No. of pulses on B Set by PULSE_CNTB (0–63 pulses) register
Low-side A frequency Set by registers:
● ON_A (11 bits at 16 MHz)
● OFF_A (11 bits at 16 MHz)
● DEADTIME (8 bits at 16 MHz)
Low-side B frequency Set by registers: ON_A (11 bits at 16 MHz), OFF_A (11 bits at 16 MHz), DEADTIME (8 bits at 16 MHz)
Mode Bits in BURST_MODE Register: 001
Mode description Low-side A is controlled by burst generator A
Low-side B through the internal micro P2.1 port
Low-side A trigger Write 1 to BURST_A_EN bit in EN_CTRL register
Low-side B trigger Controlled by 8051W software
No. of pulses on A Set by PULSE_CNTA (0–63 pulses) register
No. of pulses on B Controlled by 8051W software
Low-side A frequency Set by registers:
● ON_A (11 bits at 16 MHz)
● OFF_A (11 bits at 16 MHz)
Low-side B frequency Controlled by 8051W software
Mode Bits in BURST_MODE Register: 010
Mode description Low-side A through the internal micro P2.0 port
Low-side B is controlled by burst generator B
Low-side A trigger Controlled by 8051W software
Low-side B trigger Write 1 to BURST_B_EN bit in EN_CTRL register
No. of pulses on A Controlled by 8051W software
No. of pulses on B Set by PULSE_CNTB (0–63 pulses) register
Low-side A frequency Controlled by 8051W software
Low-side B frequency Set by registers: ON_B (11 bits at 16 MHz) and OFF_B (11 bits at 16 MHz)
Mode Bits in BURST_MODE Register: 011
Mode description Low-side A is controlled by burst generator A
Low-side B is controlled by burst generator B
Low-side A trigger Write 1 to BURST_A_EN bit in EN_CTRL register
Low-Side B trigger Write 1 to BURST_B_EN bit in EN_CTRL register
No. of pulses on A Set by PULSE_CNTA (0–63 pulses) register
No. of pulses on B Set by PULSE_CNTB (0–63 pulses) register
Low-side A frequency Set by registers: ON_A (11 bits at 16 MHz) and OFF_A (11 bits at 16 MHz)
Low-side B frequency Set by registers: ON_B (11 bits at 16 MHz) and OFF_B (11 bits at 16 MHz)
Mode Bits in BURST_MODE Register: 100
Mode description Low-side A through the internal micro P2.0 port
Low-side B through the internal micro P2.1 port
Low-side A trigger Controlled by 8051W software
Low-side B trigger Controlled by 8051W software
No. of pulses on A Controlled by 8051W software
No. of pulses on B Controlled by 8051W software
Low-side A frequency Controlled by 8051W software
Low-side B frequency Controlled by 8051W software
Mode Bits in BURST_MODE Register: 101
Mode description Reserved
Mode Bits in BURST_MODE Register: 110
Mode description Reserved
Mode Bits in BURST_MODE Register: 111
Mode description Reserved

Figure 14 shows the relationship of BURST_OUTx.

PGA450-Q1 pulse_tim_lds185.gif Figure 14. Timing Diagram Showing the Usage of ON Register, OFF Register and PULSE COUNT Register Values

The relationship between the ONTIME, OFFTIME, and DEADTIME values in the push-pull configurations are shown in Figure 15.

PGA450-Q1 DEADTIME_tim_lds185.gif Figure 15. Timing Diagram Showing the Relationship Between ONTIME, OFFTIME, and DEADTIME Registers in the Push-Pull Configuration

Table 5 lists the 8051W port pins used to drive the OUTA and OUTB pins are listed in the 8051W drive mode.

Table 5. OUTA/OUTB Pin Map

PGA450-Q1 PIN 8051W PORT
OUTA 2.0
OUTB 2.1

7.3.6 Low-Noise Amplifier

This block is the analog front-end that interfaces with the transducer directly. The echo signal is coupled through an external capacitor so that only the AC component of the transducer voltage is passed to the low-noise amplifier (LNA). The LNA outputs an amplified version of the transducer voltage with a DC offset that is equal to the mid-scale of the analog-to-digital converter (ADC).

The LNA gain is configurable by setting the LNA_GAIN1 and LNA_GAIN0 bits in the CONTROL_1 register to the appropriate values.

PGA450-Q1 lo_noise_amp_lds185.gif Figure 16. Low-Noise Amplifier

7.3.7 Analog-to-Digital Converter

The 12-bit successive approximation register (SAR) analog-to-digital converter converts the analog voltage from the echo-processing circuit into a digital word. The converted digital word is processed by the bandpass filter. The ADC is dedicated to the echo-processing signal path and is only enabled in active mode.

7.3.8 Digital Data Path

The digital datapath processes the AD sample to extract the peak profile of the echo. The output of the digital datapath is stored in the FIFO RAM.

Figure 17 shows the digital datapath.

PGA450-Q1 dig_path_lds185.gif Figure 17. Digital Data Path

The digital datapath has the following components:

  • Bandpass filter
  • Rectifier
  • Peak extractor
  • Downsampler
  • Low-pass filter

Each of the digital datapath components is described in the following subsections.

7.3.8.1 Bandpass Filter (BPF)

The echo signal is an amplitude-modulated signal with the underlying carrier frequency equal to the drive frequency of the ultrasonic transducer. The bandpass filter block allows frequencies near the drive frequency to pass to downstream signal blocks.

The bandpass filter is a second-order Butterworth IIR filter. The user can configure the center frequency and the bandwidth of the filter by writing specific values to coefficient registers BPF_B1, BPF_A2, and BPF_A3.

Table 7 lists the values (in hex) that must be written to the coefficient registers to realize a bandpass filter of specific center frequency and bandwidth (or Q).

NOTE

The stability of the filter is not assured if values other than those listed in Table 7 are written to the registers.

Table 6. Bandpass Filter Coefficient Values

BW (kHz) B1 (Hex) A3 (Hex)
4 32D F9A5
4.5 392 F8DD
5 3F6 F815
5.5 459 F74D
6 4BD F687
6.5 520 F5C1
7 582 F4FB

Table 7. Bandpass Filter Coefficient Values

CF (kHz) BW (kHz) A2 (Hex)
39 4 F54A
5 F48B
6 F3CD
7 F311
40 4 F4E6
5 F427
6 F36A
7 F2AE
41 4 F480
5 F3C1
6 F304
7 F249
42 4 F417
5 F358
6 F29C
7 F1E1
43 4 F3AC
5 F2ED
6 F231
7 F176
44 4 F33E
5 F280
6 F1C4
7 F10A
45 4 F2CE
5 F210
6 F154
7 F09A
46 4 F25B
5 F19E
6 F0E2
7 F029
47 4 F1E6
5 F129
6 F06E
7 EFB5
48 4 F16E
5 F0B2
6 EFF7
7 EF3E
49 4 F0F4
5 F038
6 EF7E
7 EEC5
50 4 F078
5 EFBC
6 EF02
7 EE4A
51 4 EFF9
5 EF3E
6 EE84
7 EDCC
52 4 EF78
5 EEBD
6 EE03
7 ED4C
53 4 EEF4
5 EE39
6 ED80
7 ECC9
54 4 EE6E
5 EDB4
6 ECFB
7 EC44
55 4 EDE5
5 ED2B
6 EC73
7 EBBD
56 4 ED5A
5 ECA1
6 EBE9
7 EB33
57 4 ECCD
5 EC14
6 EB5D
7 EAA7
58 4 EC3D
5 EB85
6 EACE
7 EA19
59 4 EBAB
5 EAF3
6 EA3D
7 E988
60 4 EB16
5 EA5F
6 E9A9
7 E8F5
61 4 EA7F
5 E9C8
6 E913
7 E85F
62 4 E9E6
5 E930
6 E87B
7 E7C7
63 4 E94B
5 E894
6 E7E0
7 E72D
64 4 E8AD
5 E7F7
6 E743
7 E691
65 4 E80C
5 E757
6 E6A4
7 E5F2
66 4 E769
5 E6B5
6 E602
7 E551
67 4 E6C4
5 E610
6 E55E
7 E4AD
68 4 E61D
5 E569
6 E4B8
7 E407
69 4 E573
5 E4C0
6 E40F
7 E35F
70 4 E4C7
5 E415
6 E364
7 E2B5

7.3.8.2 Rectifier

The output of the bandpass filter is a signed number. The rectifier rectifies the output of the bandpass filter to create a positive number.

7.3.8.3 Peak Extractor

The peak extractor in the PGA450-Q1 is a simple moving-peak algorithm. Specifically, the output of the peak extractor is updated if the input to the peak extractor is greater than the previous output of the peak extractor. This algorithm is summarized in Equation 1.

Equation 1. y[k] = {y[k – 1], if y[k – 1] > Px[k], otherwise x[k]}

where

  • y is the output of the peak extractor
  • x is the input to the peak extractor
  • k is the discrete-time step

Figure 18 shows the peak extractor algorithm.

PGA450-Q1 peak_ext_lds185.gif Figure 18. Peak Extractor

7.3.8.4 Downsample

The downsample block performs two functions:

  • Generates the reset signal for the peak extractor shown in Figure 18.
  • Generates the output.

The downsample rate can be configured by the user by writing to the downsample register. If the output of the peak extractor must be low-pass filtered before storing it in the FIFO, then the allowable values for the downsample register for the low-pass filter correctly are from 25 to 50; that is:

Equation 2. 25 ≤ DOWNSAMPLE ≤ 50

However, if the user does not need to low-pass filter the output before storing to the FIFO, then the user can configure the DOWNSAMPLE register value to any value between 1 and 63.

The downsample block has a counter which starts at 0 and counts up to the values programmed in the DOWNSAMPLE register. When the count reaches the value in the DOWNSAMPLE register, the counter inside the downsample block is reset to 0. Furthermore, the downsample block generates a reset to the peak extractor. This reset signal sets the output of the peak extractor to 0.

The data output rate of the downsample block is:

Equation 3. OUTPUT RATE OF DOWNSAMPLE RATE = DOWNSAMPLE × 1 µs.

7.3.8.5 Low-Pass Filter

The output of the downsample block can be filtered by a low-pass filter. The low-pass filter in the PGA450-Q1 device is a first-order Butterworth IIR filter with a configurable cutoff frequency.

The user can configure the cutoff frequency of the filter by writing specific values to coefficient registers LPF_B1 and LPF_A2. Note that for the same desired cutoff frequency, the coefficient values depend on the configured DOWNSAMPLE register.

Table 8 lists the values (in hex) that must be written to the coefficient registers to realize a low-pass filter of a specific cutoff frequency. The stability of the filter is not assured if values other than those listed in the table are written to the registers.

Table 8. Low-Pass Filter Coefficient Values

CUTOFF (kHz) DOWNSAMPLE (Hex) B1 (Hex) A2 (Hex)
0.5 19 4D7 7652
1A 506 75F3
1B 536 7594
1C 565 7535
1D 595 74D7
1E 5C4 7479
1F 5F3 741B
20 622 73BD
21 650 7360
22 67F 7302
23 6AD 72A5
24 6DC 7249
25 70A 71EC
26 738 7190
27 766 7134
28 794 70D9
29 7C1 707E
2A 7EF 7022
2B 81C 6FC8
2C 84A 6F6D
2D 877 6F13
2E 8A4 6EB9
2F 8D1 6E5F
30 8FD 6E05
31 92A 6DAC
32 957 6D53
1.0 19 957 6D53
1A 9B0 6CA1
1B A08 6BF0
1C A60 6B41
1D AB7 6A92
1E B0E 69E5
1F B64 6937
20 BBA 688B
21 C10 67E0
22 C65 6736
23 CBA 668C
24 D0E 65E4
25 D62 653C
26 DB6 6495
27 E09 63EF
28 E5B 6349
29 EAE 62A5
2A EFF 6201
2B F51 615E
2C FA2 60BC
2D FF3 601B
2E 1043 5F7A
2F 1093 5EDA
30 10E2 5E3B
31 1132 5D9D
32 1180 5CFF
1.5 19 D8C 64E8
1A E09 63EF
1B E84 62F7
1C EFF 6201
1D F79 610D
1E FF3 601B
1F 106B 5F2A
20 1000 5E3B
21 1159 5D4E
22 11CF 5C62
23 1244 5B78
24 12B8 5A90
25 132C 59A9
26 139E 58C4
27 1410 57E0
28 1481 56FD
29 14F2 561C
2A 1562 553D
2B 15D1 545E
2C 163F 5381
2D 16AD 52A6
2E 171A 51CC
2F 1786 50F3
30 17F2 501C
31 185D 4F45
32 18C8 4E70
2.0 19 1180 5CFF
1A 121D 5BC6
1B 12B8 5A90
1C 1352 595C
1D 13EA 582B
1E 1481 56FD
1F 1517 55D1
20 15AC 54A8
21 163F 5381
22 16D1 525D
23 1762 513B
24 17F2 501C
25 1881 4EFE
26 190F 4DE3
27 199B 4CCA
28 1A27 4BB3
29 1AB1 4A9E
2A 1B3A 498B
2B 1BC3 487A
2C 1C4A 476B
2D 1CD1 465E
2E 1D56 4553
2F 1DDB 444A
30 1E5F 4342
31 1EE2 423C
32 1F64 4138
2.5 19 153D 5587
1A 15F6 5415
1B 16AD 52A6
1C 1762 513B
1D 1816 4FD4
1E 18C8 4E70
1F 1978 4D10
20 1A27 4BB3
21 1AD3 4A59
22 1B7F 4903
23 1C29 47AF
24 1CD1 465E
25 1D78 4511
26 1E1D 43C6
27 1EC1 427E
28 1F64 4138
29 2005 3FF5
2A 20A6 3EB5
2B 2145 3D77
2C 21E2 3C3B
2D 227F 3B02
2E 231A 39CB
2F 23B5 3897
30 244E 3764
31 24E6 3633
32 257E 3505
3.0 19 18C8 4E70
1A 199B 4CCA
1B 1A6C 4B28
1C 1B3A 498B
1D 1C07 47F3
1E 1CD1 465E
1F 1D99 44CE
20 1E5F 4342
21 1F23 41BA
22 1FE5 4036
23 20A6 3EB5
24 2164 3D38
25 2221 3BBE
26 22DC 3A47
27 2396 38D4
28 244E 3764
29 2505 35F7
2A 25BA 348D
2B 266E 3325
2C 2720 31C0
2D 27D1 305E
2E 2881 2EFE
2F 292F 2DA1
30 29DD 2C46
31 2A89 2AED
32 2B35 2997
3.5 19 1C29 47AF
1A 1D14 45D9
1B 1DFC 4408
1C 1EE2 423C
1D 1FC5 4076
1E 20A6 3EB5
1F 2184 3CF8
20 2260 3B41
21 2339 398D
22 2411 37DE
23 24E6 3633
24 25BA 348D
25 268B 32E9
26 275B 314A
27 2829 2FAE
28 28F5 2E15
29 29C0 2C80
2A 2A89 2AED
2B 2B51 295E
2C 2C17 27D2
2D 2CDC 2648
2E 2DA0 24C0
2F 2E62 233C
30 2F23 21B9
31 2FE4 2039
32 30A3 1EBB
4.0 19 1F64 4138
1A 2066 3F35
1B 2164 3D38
1C 2260 3B41
1D 2358 3950
1E 244E 3764
1F 2541 357E
20 2632 339D
21 2720 31C0
22 280C 2FE8
23 28F5 2E15
24 29DD 2C46
25 2AC2 2A7B
26 2BA6 28B4
27 2C88 26F0
28 2D68 2530
29 2E46 2373
2A 2F23 21B9
2B 2FFF 2002
2C 30D9 1E4E
2D 31B2 1C9D
2E 3289 1AED
2F 3360 1940
30 3435 1796
31 350A 15ED
32 35DD 1446

7.3.8.6 Datapath Output Format Control

The output of the datapath is stored in the ECHO DATA register. The output of the datapath register is updated at the rate determined by the value in the DOWNSAMPLE register.

The output of the digital datapath is also stored in the FIFO RAM. The user can configure the data stored in the FIFO RAM by writing values to the mode bits in the FIFO control (FIFO_CTRL) register.

Table 9 lists the output format of the digital datapath that is stored in the FIFO.

Table 9. Digital Datapath Output Format

MODE BITS OUTPUT FORMAT DESCRIPTION
0b00 12 bits All 12 bits of the digital datapath output are stored in the FIFO. Note that storing 12 bits consumes 2 bytes of the FIFO RAM.
0b01 8 most-significant bits The upper 8 bits of the 12-bit digital datapath output are stored in the FIFO.
0b10 8 least-significant bits The lower 8 bits of the 12-bit digital datapath output are stored in the FIFO, if all the upper 4 bits of the digital datapath output are 0s. However, if one of the upper 4 bits of the digital datapath is 1, then 0xFF is stored to the FIFO.
0b11 8 middle bits Bits 10 through 3 of the 12-bit digital datapath output are stored in the FIFO, if the upper 2 bits of the digital datapath output are 0s. However, if one of the upper 2 bits of the digital datapath is 1, then 0xFF is stored to the FIFO.

7.3.8.7 Datapath Activation and Blanking Timer

The digital datapath calculations can be enabled or disabled using the ECHO_EN bit in the enable control (EN_CTRL) register. When the ECHO_EN bit is set to 0, the digital datapath is disabled; that is, the datapath does not perform the calculations and does not update the FIFO RAM. Furthermore, the history of the band-pass and low-pass filters is reset to 0.

When the user sets ECHO_EN to 1, the digital datapath begins the computation. However, the output of the datapath does not immediately start filling the FIFO RAM. Rather, the output of the digital datapath is updated into the FIFO RAM when the user-configured BLANKING_TIMER value has expired.

The user-configurable BLANKING_TIMER register is an 8-bit-register with 16-µs resolution per bit. In other words, the user can set the blanking timer value from 0 µs to 4.08 ms in steps of 16 µs.

Figure 19 shows the state of the digital datapath based on the enable or disable state of ECHO_EN and the BLANKING_TIMER register value.

PGA450-Q1 blank_timr_lds185.gif Figure 19. States of Digital Datapath

7.3.8.8 Digital Datapath Output Mode

The digital datapath output is available in the analog-voltage mode on the DACO pin with the following constraints:

  • The DAC is an 8-bit DAC. The DAC output works only in the 8-bit MSB, 8-bit LSB, or 8-bit middle-significant-bits modes of the digital datapath output.
  • The DAC output voltage range is 0.133 V to 1.125 V with 8-bit resolution. The digital datapath output is directly scaled to the analog output voltage in this range.
  • The DAC output voltage resolution is 1 / 255 V.
  • An external amplifier or buffer may be needed before the output of the DAC can be used to drive a load or viewed on a scope.
  • The ANALOG_MUX ESFR is used to control the availability of the DAC output on DACO pin. The reset state of the DACO is NONE which means that no internal signal is available until after POR.
  • When the digital datapath output on DACO is enabled, the temperature sensor register (TEMP_SENS) is not updated.

To enable the temperature sensor or the digital datapath output, the TS_DAC_EN bit in TEMP_DAC_CTRL ESFR must be set to 1. The TS_DAC_mode bit determines whether the DAC is used for the temperature sensor or the digital datapath output.

PGA450-Q1 dig_datapath_output.gif
1. IF the FIFO_CTRL bit is in 8-bit mode, output datapath, otherwise output 8-bit MSB.
Figure 20. Availability of Digital Datapath Output as an Analog Output on DACO

7.3.9 Transducer Saturation Time

The transducer saturation block is used to measure the saturation time of the transducer. The measurement is based on the voltage at the LIM pin of the PGA450-Q1.

The transducer saturation time is defined as the time from when the SAT_EN bit in the enable control (EN_CTRL) register is set to 1 to the time when the voltage at LIM falls below the programmable threshold and stays below that threshold for the programmable deglitch time.

Figure 21 shows the block diagram of the transducer saturation-time measurement block. The saturation-time measurement is accomplished with the following registers.

  • EN_CTRL register — set the SAT_EN bit.
  • CONTROL_1 register — set the saturation threshold with the SAT_SEL1 and SAT_SEL0 bits
  • SAT_DEGLITCH register (the saturation deglitch time register) — 8 bits at 2 µs resolution
  • SAT_TIME register (the saturation time capture register) — 8 bits at 16 µs
  • STATUS2 register — set the SAT_DONE bit
PGA450-Q1 sat_block_lds185.gif Figure 21. Transducer Saturation-Time Measurement Block

Figure 22 shows the timing diagram of the saturation-time measurement. The figure shows that an internal saturation timer starts when the SAT_EN bit in the EN_CTRL register is set to 1. The saturation-time measurement block then monitors only the positive voltage on the LIM pin. When this voltage goes below the programmed saturation threshold, the saturation-time deglitch timer is started.

NOTES:

  • When the deglitch timer reaches the programmed deglitch time in the SAT_DEGLITCH register, the value in the internal saturation timer is captured into the SAT_TIME register and the SAT_DONE bit is set to 1.
  • If the voltage at the LIM pin does not go below the programmed threshold after the SAT_EN bit is set to 1, then the SAT_DONE bit remains at 0. In this case, the maximum value of the SAT_TIME register is 0xFF.
  • Setting the SAT_EN bit to 0 resets the SAT_TIME register to 0 and sets the SAT_DONE bit to 0.

PGA450-Q1 saturation_lds185.gif Figure 22. Timing Diagram Showing the Measurement of Transducer Saturation Time

7.3.10 Temperature Sensor

The PGA450-Q1 has an on-chip temperature sensor that provides a signed 8-bit 2s-complement output (MSB is the sign bit) with code 0 corresponding to 30°C. The temperature sensor has a typical gain of 1.75°C / code. The temperature sensor is disabled by default. The TS_DAC_EN bit in the TEMP_DAC_CTRL register must be set to enable the temperature sensor. The conversion time is typically 1.4 ms.

Equation 4 is the nominal equation for the temperature in °C.

Equation 4. Temperature = 1.75 × ADC_CODE + 30

7.3.11 Free-Running Timer

The PGA450-Q1 includes a 16-bit free-running timer that operates at a resolution of 1 µs. This timer can be used to synchronize echo transit times between two different PGA450-Q1 devices by the master ECU in triangulation applications.

This timer starts from a reset value of 0 at POR and counts up. When the timer values reaches 0xFFFF, the timer rolls over to 0x0000.

The value of the free-running timer is not visible to the 8051W. However, the instantaneous value of the free-running timer can be captured into the free-running timer (FRT) capture ESFR by setting the CAP_FR_TIMER bit in the ENABLE CONTROL register to 1.

The FRT ESFR is a shadow of the free-running timer. The shadow register is not updated continuously. To copy the current value of the free-running timer into the ESFR, do the following:

  • Write a 1 to the CAP_FR_TIMER bit in the EN_CTRL register.
  • Read the FRT register.

See the Register Maps section for descriptions of the registers.

NOTE

The reason for implementing the FRT register as a shadow register is to allow the reading of the MSB and LSB coherently. The transfer from the free-running timer value to the FRT register is a 16-bit transfer and it is coherent. Because the 8051 can read only 1 byte at a time, coherency is maintained between two MSB and LSB reads of the FRT register because the FRT register value does not change between the reads of the MSB and LSB.

7.3.12 GPIOs

The GPIOx pins on the PGA450-Q1 can be used as either general-purpose inputs and outputs (I/Os) or can be used as I/Os for specific functionality.

In the general-purpose I/Os mode, the GPIOx pins are connected to specific 8051W port pins. User software can be used to control the state of the device pins by controlling the appropriate I/O port SFRs in the 8051W. Table 10 lists the mapping of the PGA450-Q1 GPIOx pins to specific 8051W ports.

Table 10. GPIOx Pin Map

PGA450-Q1 Pin 8051W PORT
GPIO1 3.4
GPIO2 3.5

7.3.13 8051W UART

The TxD and RxD pins on the PGA450-Q1 are connected to the 8051W UART. These two pins can be used either for software debugging or for implementing application-specific protocols.

Table 11. TxD and RxD Pin Functionality

PGA450-Q1 Pin 8051W PORT
TxD 3.1
RxD 3.0

7.3.14 8051 WARP Core

The 8051 WARP core is an exceptionally high-performance version of this popular 8-bit microcontroller, requiring just 2 clocks per machine cycle rather than the 12 clocks per cycle of the industry-standard device, while keeping functional compatibility with the standard part. The 8051W core in the PGA450-Q1 includes two 16-bit timers and a serial interface.

PGA450-Q1 warp_8051W_1.gif Figure 23. 8051W Core

7.3.15 Memory

Table 12 lists the PGA450-Q1 memory types.

Table 12. Memory

MEMORY SIZE DESCRITPTION
FIFO_RAM(1) 768 bytes Digital datapath output
Scratchpad RAM 256 bytes Used for software variables
OTP 8K bytes Program code
EEPROM 32 bytes Configuration data
DEVELOPMENT RAM 8K bytes Program code during development
(1) FIFO is needed to allow a second scan of the digital datapath output. The minimum needed for the second scan is 512 bytes. Dual-port capability is needed so that digital datapath can fill and the microprocessor can read simultaneously. If a true dual port cannot be implemented, then an interrupt once every X number of bytes are available works. X can be 32 to 128 bytes. 768 bytes are needed to address the microprocessor throughput issue. If throughput of the microprocessor can be improved, 256 bytes could be sufficient.

7.3.15.1 FIFO Memory for Digital Datapath Output

The FIFO memory is volatile RAM memory. The output of the digital datapath is stored in the FIFO memory.

The FIFO memory is memory-mapped to the 8051W external memory address space. The contents of the FIFO memory are accessible to the 8051W core.

The FIFO memory is a dual-port RAM; that is, that the 8051W can read the FIFO contents while the digital datapath is filling the memory.

The FIFO memory also has a FIFO pointer, which is stored in the FIFO_POINTER register. The FIFO pointer behavior is as follows:

  • The FIFO pointer has the address of the last FIFO byte that was filled by the digital datapath.
  • If the digital datapath has been configured to output data in 12-bit format, the FIFO pointer value increases by 2.
  • If the digital datapath outputs data in 8-bit format, the FIFO pointer value increases by 1.

The FIFO pointer is reset to 0 at power up. Similarly, when the ECHO_EN bit in the EN_CTRL register is set to 1, the FIFO pointer value is reset to 0. However, the FIFO memory contents are not cleared to 0.

PGA450-Q1 FIFO_lds185.gif Figure 24. FIFO Memory Organization

7.3.15.2 OTP Memory for Program

The programming voltage for the OTP memory must be provided externally, because the device does not have a voltage regulator to generate the OTP programming voltage. This voltage must be provided on the VPROG_OTP pin.

7.3.15.2.1 OTP Security

The PGA450-Q1 provides the ability to LOCK the OTP. The OTP memory cannot be read or programmed through the SPI. This feature is called OTP security.

PGA450-Q1 sec_blk_lds185.gif Figure 25. Connection Between the 8051W Core and OTP Security Block

The following is the procedure to LOCK and UNLOCK the OTP

  • To LOCK the OTP memory, 8051W P0 should be set to 0xAA in software.
  • To UNLOCK the OTP memory, 8051W P0 should be set to 0x00 in software.

NOTE

  • Writing to P0 immediately after the 8051W reset is deasserted (immediately after the 8051W starts running software) is recommended.
  • When the OTP memory is in LOCK state, the 8051W processor has access to OTP memory; that is, program execution can continue.
  • If the 8051W processor is put in the reset state after a LOCK instruction in software has been executed, the OTP memory cannot be accessed through the SPI.

7.3.15.2.2 OTP Programming

Both the 8051W microprocessor and the SPI can access the 8K OTP memory. The 8051W has read access only. The SPI has read access and program access.

Prior to starting the OTP programming process, raising the VPROG_OTP pin on the PGA450-Q1 to 8 V is required. When the voltage on this device pin reaches this level, the OTP programming mode is enabled.

NOTE

The OTP programming voltage should not be connected to the pin for an extended period of time.

CAUTION

Do not power up OR power down the PGA450-Q1 with the VPROG_OTP pin set to 8 V, this may cause unrecoverable corruption to the OTP data.

Programming of the OTP must be done one address at a time. Each address can only be programmed once. After an address is programmed, it cannot be programmed again. Programming a section of the OTP address space and then programming an additional section of OTP address space at a later time is possible.

To program a byte of OTP, four bytes must be sent through SPI. The first byte is 0x07 indicating an OTP write operation. The next 2 bytes contain the address of the target OTP location and the last byte contains the data.

There should be at least 100 µs between two successive OTP write instructions. This time is needed to ensure the proper programming of the OTP cell. Violation of this might cause data retention issues for the OTP memory during the lifetime of the device. With a 4-MHz SCK frequency, it takes approximately 1 s to program the entire 8K address space of the OTP.

The following is the OTP memory programming procedure:

  1. After power up, set the VPROG_OTP pin to 8 V.
  2. Send an OTP write command through the SPI.
  3. The CS pin is set to HIGH at least 100 µs for the OTP programming process to complete. Do not perform any SPI write operations to the OTP during the OTP programming process.
  4. Repeat Steps 2 and 3 until all desired OTP addresses have been programmed.
  5. Before powering down the PGA450-Q1 device, disconnect the 8-V supply to VPROG_OTP pin.

7.3.15.3 EEPROM Memory for Data

Figure 26 shows the EEPROM structure in the PGA450-Q1 device. The EEPROM structure in PGA450-Q1 includes volatile cache. The cache has one-to-one mapping with the nonvolatile EEPROM memory cells. The EEPROM cache is mapped into the external memory space of the 8051W memory map.

PGA450-Q1 EEPROM_if_lds185.gif Figure 26. Structure of EEPROM Interface

7.3.15.3.1 EEPROM Memory Organization

7.3.15.3.1.1 EEPROM Cache

The EEPROM cache serves as temporary storage of data being transferred to or from EEPROM. Data transferred to the EEPROM cache from either SPI or from the M8051 is byte-addressable, and one byte at time can be written to or read from the EEPROM cache. Selection of the EEPROM cache interface is determined by the internally generated MUX-select bit. The MUX-select bit is by default set to 8051W access. The EEPROM cache is accessible to the SPI when the 8051W is put in reset in the test mode.

When programming to EEPROM through the SPI, the EEPROM cache holds the programming data for the amount of time necessary to complete the EEPROM programming process.

7.3.15.3.1.2 EEPROM Memory Cells

The EEPROM memory cells are nonvolatile. The contents of the cache are programmed into the EEPROM when the 8051W requests the programming. The cache is loaded with the contents of the EEPROM memory cells at power up.

7.3.15.3.2 Programming EEPROM Through the 8051W and SPI

The following is the EEPROM memory programming procedure:

  1. Write data to EEPROM cache
    • Use the 8051W MOVX assembly instruction to place data in external memory addresses 0x0400 through 0x041F.
  2. Write a 1 to the WRITE bit in the EE_CTRL register.
  3. Continuously poll the EE_STATUS bit in EE_CTRL register for the programming status. The EEPROM programming requires 70 ms to complete.

7.3.15.3.3 Reloading From EEPROM Cells Through the 8051W and SPI

The following is the reloading procedure:

  1. Write a 1 to the RELOAD bit in the EE_CTRL register which causes the EEPROM cells to be loaded into cache. The reload operation requires 125 µs to complete.
  2. Use the 8051W MOVX assembly instruction to transfer data from the cache to internal RAM.

7.3.16 LIN 2.1 Slave and Buffered SCI

The PGA450-Q1 implements the LIN 2.1 compliant physical layer. This physical layer can be used to communicate data between the PGA450-Q1 and the master ECU.

The PGA450-Q1 can be configured to operate in the LIN 2.1 slave-protocol mode or SCI buffered mode. If the device is configured in LIN 2.1 slave-protocol mode, then the protocol layer described in Section 2.1 of the LIN 2.1 specification must be used to communicate with the PGA450-Q1. The device can only be configured as a slave; that is, the PGA450-Q1 cannot be used as a master.

The LIN 2.1 slave protocol implemented in PGA450-Q1 has the following exceptions:

  • No wake-up (Section 2.6.2 of LIN 2.1). The device cannot be put to sleep and be woken through the LIN.
  • No transport layer in digital logic (Section 3 of LIN 2.1)
  • No node configuration and identification services in digital (Section 4 of LIN 2.1)
  • No diagnostic layer in digital logic (Section 5 of LIN 2.1)
  • Communication baud rate is fixed at 19.2 kBPS. That is, the device baud rate is not configurable.

The PGA450-Q1 can also be configured to operate in SCI buffered mode. In this mode, no specific protocol is needed to communicate with the PGA450-Q1. The user has the choice to implement the protocol in software. The device provides the ability either to transmit or to receive 8 bytes of data without any intervention from 8051W software.

The user selects either LIN 2.1 slave mode or SCI buffered mode by setting the LIN_SCI bit in the LIN_SCI_SEL register. If the LIN_SCI bit is changed from LIN mode to SCI mode or vice versa, the communication protocol is reset.

7.3.16.1 Physical Layer

The physical layer inside the PGA450-Q1 is compliant with the LIN 2.1 specification. Figure 27 shows the line driver and receiver schematic illustrated in the LIN 2.1 specification. The inner dashed box in Figure 27 identifies the section that has been implemented in the PGA450-Q1.

PGA450-Q1 phy_layer_lds185.gif
VSUP is the internal supply for electronics.
Figure 27. LIN Physical Layer in LIN 2.1 Specification

Figure 28 shows the schematic of the LIN 2.1 physical layer in PGA450-Q1. This figure infers that the PGA450-Q1 implements the LIN 2.1 slave physical layer.

PGA450-Q1 LIN_layer_lds185.gif Figure 28. LIN Physical Layer in the PGA450-Q1

7.3.16.2 LIN Slave Mode

This section describes the LIN slave protocol mode of operation of the PGA450-Q1.

7.3.16.2.1 LIN Frame

This peripheral handles the LIN 2.1 frames shown in Figure 29. The LIN 2.1 frame has a break field, sync field, PID field, data fields, and checksum field.

PGA450-Q1 LIN_Frame_1.gif Figure 29. LIN Frame From the LIN 2.1 Specification

Figure 30 shows the LIN byte field. This figure shows that the LIN byte field has 1 start bit and 1 stop bit. The least-significant bit (LSB) is transmitted first.

PGA450-Q1 Byte_field_lds185.gif Figure 30. LIN Byte Field From the LIN 2.1 Specification
PGA450-Q1 break_field_lds185.gif Figure 31. LIN Break Field From the LIN 2.1 Specification

A break field is always generated by the master task (in the master node) and it shall be at least 13 nominal bit times of dominant value, followed by a break delimiter.

PGA450-Q1 Byte_field_lds185.gif Figure 32. LIN Sync Field From the LIN 2.1 Specification

Sync is a byte field with the data value 0x55.

7.3.16.2.2 LIN Registers

Figure 33 shows all the registers associated with the LIN peripheral. The LIN PID, RX DATA0–7 and TX DATA0–7 have unique registers associated with them.

PGA450-Q1 LIN_registers_lds185.gif Figure 33. LIN Registers

NOTE

The PGA450-Q1 LIN slave protocol does not decode the LIN PID registers. The decoding logic for the PID registers must be implemented in 8051W software.

7.3.16.2.3 LIN Interrupts

Figure 34 shows the four interrupts that the LIN slave protocol generates. These interrupts are:

    SYNC interrupt: This interrupt is generated by the LIN slave protocol when the SYNC field is received. Note that the SYNC field interrupt is generated regardless of whether the subsequent LIN frame fields are received. Thus, the customers can use the BREAK+SYNC fields to synchronize the internal clock and use other protocols for communication.
    PID interrupt: This interrupt is generated by the LIN slave protocol when the PID is received and the PID does not have a parity error.
    Rx interrupt: This interrupt is generated by the LIN slave protocol when the PGA450-Q1 receives the LIN data. The interrupt is generated only when the checksum is received and the checksum has no errors. The device performs the enhanced checksum calculation. According to the LIN 2.1 specification, the enhanced checksum is the checksum calculation over the data bytes and the protected identifier byte.
    Tx interrupt: This interrupt is generated by the LIN slave protocol when the PGA450-Q1 transmits data. The interrupt is generated at the end of the checksum transmission.

PGA450-Q1 LIN_interrupts_lds185.gif Figure 34. LIN Interrupts

The PID interrupt processing shown in Figure 34 is for a transmit message.

7.3.16.2.4 LIN Slave Configuration

The LIN slave in the PGA450-Q1 is configurable. This section describes the available configurations. These configurations are not applicable if the PGA450-Q1 is set up to operate in SCI buffered mode.

The LIN configuration register, LIN_CFG, is used to configure the LIN slave in the PGA450-Q1. The following sections describe the possible configurations.

7.3.16.2.4.1 LIN Frame-Control Configuration

The PGA450-Q1 has three bits that control the behavior of the PGA450-Q1 when a LIN frame is received.

    IGNORE_DIAG: This bit controls the mode of operation of the LIN slave controller when the PID is received.

    If this bit is set to 0, then the LIN slave controller waits for data bytes after the PID field in the LIN frame is received.

    If this bit is set to 1, then the LIN slave controller finishes the current frame after the PID is received and waits for the next LIN frame.

    HOLD: This bit determines whether the LIN frame received by PGA450-Q1 is processed or ignored.

    If this bit is set to 1 (which is the power ON reset state), then the received LIN frame is ignored.

    If this bit is set to 0, then the received LIN frame is not ignored.

    CS_METHOD: This bit controls whether the checksum is classic checksum or enhanced checksum.

    If this bit is set to 0 (which is power ON reset state), the LIN protocol calculates and validates the checksum using the classic checksum method.

    If this bit is set to 1, the LIN protocol calculates and validates the checksum using the enhanced checksum method.

7.3.16.2.4.2 LIN Timing-Control Configuration

The PGA450-Q1 has two bits that control the various timing parameters of the LIN frame.

    INTERBYTE_SPACE: This bit controls the duration of the time between the data fields when PGA450-Q1 is transmitting data.

    If this bit is set to 0, then the interbyte space is equal to 1 bit.

    If this bit is set to 1, then the interbyte space is equal to 2 bits.

    BIT_TOL:This bit controls the tolerance of bit time that is used in the LIN frame timing diagnostics.

    If this bit is set to 0, the bit time tolerance is 15% of the bit time determined during the LIN SYNC field.

    If this bit is set to 1, the bit time tolerance is 30% of the bit time determined during the LIN SYNC field.

7.3.16.2.5 LIN Slave-Protocol State Machine

Figure 35 shows the LIN slave-protocol state machine implemented inside PGA450-Q1. The figure shows that the protocol enters the Wait-for-Break-Field state on power up. When the master sends the break field, the state machine transitions into the Wait-for-Sync-Field state only if the HOLD bit in the LIN_CFG register is set to 0. Otherwise, the LIN protocol return to the Wait-for-Break-Field state.

After the sync field is received, the state machine generates the SYNC field interrupt and transitions into the Wait-for-PID-Field state. After the PID field is received, the PID parity is checked. If the parity has an error, then the state machine transitions back to the Wait-for-Break-Field state. If there is no parity error, then the state machine generates the PID interrupt to the 8051W.

The user must write software to service the PID interrupt. In the PID interrupt service routine, the user determines whether the received PID corresponds to Rx message or Tx message.

In the case of an Rx message, the state machine waits for all the data bytes to be received. The number of data bytes received is determined by the value in the DATA_CNT register. When all the data bytes are received, then the state machine calculates the checksum. If the calculated checksum matches the received checksum, then the state machine generates an Rx interrupt to the 8051W. Otherwise, the state machine transitions back to Wait-for-Break-Field state.

In the case of a Tx Message, the state machine calculates the checksum based on the data after the 8051W loads the transmit buffers and the DATA_CNT register. At the end of frame transmission (that is, when the checksum is transmitted), the state machine generates a Tx interrupt to the 8051W.

PGA450-Q1 cont_state_lds185.gif

NOTE:

When the LIN_SCI bit is changed from LIN mode to SCI mode while the LIN mode is in any of the states, the LIN state machine goes to the Wait-for-Break-Field state.
Figure 35. LIN Controller State Machine

7.3.16.2.6 LIN Slave Protocol Rx

If the PID field corresponds to an Rx message, the following are the steps to receive a LIN message.

In the PID interrupt service routine, do the following:

  • Load the DATA_CNT ESFR with the expected number of Rx data bytes.
  • Set the RX_TX bit in the LIN_CTRL ESFR to 0 to receive a message.

In the Rx interrupt service routine, do the following:

  • Transfer data from the RX_DATA buffers to RAM.

See the ESFR Registers section for details on the ESFRs.

7.3.16.2.7 LIN Slave Protocol Tx

If the PID field corresponds to a Tx message, the following are the steps to transmit a LIN message.

In the PID interrupt service routine, do the following:

  • Load DATA_CNT ESFR with the number of data bytes to be transmitted.
  • Load TX_DATA buffers with the data that is to be transmitted.
  • Set the RX_TX bit in LIN_CTRL ESFR to 1 to transmit a message.

When the Tx interrupt service routine is called, the message transmission is complete. Nothing is required in the Tx interrupt service routine.

See the ESFR Registers section for details on the ESFRs.

NOTE

The LIN PID will be received and stored in the LIN_PID ESFR. This register will be cleared when the LIN message transmission or reception is complete. Therefore, to retain the value of the LIN_PID, the user has to copy the value of the ESFR to a RAM variable.

7.3.16.2.8 LIN Slave Status

The PGA450-Q1 has a LIN status (LIN_STATUS) register that has the error status of the received LIN frame.

This LIN_STATUS register can be cleared at any time by setting the CLR_ERR bit in the LIN_CFG register to 1.

7.3.16.2.8.1 LIN Slave Framing Error Status

The LIN_STATUS register in the PGA450-Q1 has the following bits that reflect any framing errors in the received LIN message:

    CHECKSUM:This bit is set to 1 if the received checksum does not match the calculated checksum.
    PARITY: This bit is set to 1 if the received PID has a parity error.
    STOP_BIT_VAL: This bit is set to 1 if the LIN bus does not go high for a stop bit right after the 8th data bit is received or transmitted. This check is done at the end of each Tx and Rx data byte.

7.3.16.2.8.2 LIN Slave Timing Error Status

The LIN_STATUS register in the PGA450-Q1 has bits that reflect any LIN timing errors in the received LIN message. The timing errors are based on Figure 36.

Table 13 lists the various timing errors in the received LIN message that are detected by the PGA450-Q1.

PGA450-Q1 tim_error_lds185.gif Figure 36. LIN Timing-Error Diagram

Table 13. LIN Timing Errors(1)

ERROR BIT DESCRIPTION LOWER ERROR LIMIT UPPER ERROR LIMIT
STOP_BIT_SHORT STOP bit received in PID or data bytes is shorter than expected. 52 µs × (1 – BIT_TOL)
SYNC_SHORT SYNC field duration is shorter than expected. 485 µs
SYNC_LONG SYNC field duration is longer than expected. 555 µs
BREAK_DEL BREAK FIELD delimiter is shorter than expected. 52 µs × (1 – BIT_TOL)
(1) BIT_TOL: Bit tolerance programmed in the LIN_CFG register. The Bit Tolerance can be either 15% or 30%.

7.3.16.3 SCI Buffered Mode

In the SCI buffered mode, the PGA450-Q1 does not implement any special frame or protocol. Up to 8 bytes can be received and transmitted without any 8051W software intervention. That is, the software either reads (in the case of receive) from the Rx data buffer or writes (in the case of transmit) to the Tx data buffer the appropriate number of bytes.

The DATA_CNT ESFR determines the buffer length. When data is received by the device, SCI generates an Rx data interrupt only after the number of bytes specified in DATA_CNT register is received.

7.3.16.3.1 SCI Buffered-Mode State Machine

Figure 37 shows the SCI buffered-mode state machine. If both the external device and the 8051W try to send data at the same time, a bus conflict occurs. This bus contention is not detected inside the PGA450-Q1.

If the external device sends more than 8 bytes (corresponding to the buffer length), then the data in the Rx data buffer is overwritten. Therefore, the 8051W has not had a chance to read the previous data in the buffer, so the data is lost.

PGA450-Q1 SCI_buff_lds185.gif Figure 37. SCI Buffered-Mode State Machine

7.3.16.3.2 SCI Buffered-Mode Rx

The following are the steps to receive data on SCI:

  • In software, do the following:
    • Load DATA_CNT ESFR with the expected number of Rx data bytes.
    • Set the RX_TX bit in LIN_CTRL ESFR to 0 to Rx a message.
  • In the Rx interrupt service routine, do the following:
    • Transfer data from the RX_DATA buffers to RAM.

7.3.16.3.3 SCI Buffered-Mode Tx

The following are the steps to transmit data on SCI:

  • In software, do the following:
    • Load DATA_CNT ESFR with the number of data bytes to be transmitted.
    • Load TX_DATA buffers with the data to be transmitted.
    • Set the SCI_TX_EN bit in DP_SCI_CTRL ESFR to 1 to Tx a message.
    • Set the RX_TX bit in LIN_CTRL ESFR to 1 to Tx a message.
  • When the Tx interrupt service routine is called, the message transmission is complete. Nothing is required in the Tx interrupt service routine.

NOTE

DATA_CNT in SCI buffered mode: The minimum value for DATA_CNT in SCI buffered mode is 2; that is, when the device is configured to operate in SCI buffered mode, the device can receive or transmit a minimum of 2 bytes.

7.3.16.4 Connection of LIN Pin to 8051W

The LIN transceiver is connected to the 8051W I/O as shown in Figure 38.

The state of the LIN pin can be read by software by reading 8051W port 3, pin 2 and pin 3. Similarly, 8051W port 2, pin 3 can be used to drive the TX pin of the transceiver.

The state of the Rx pin from the transceiver should be inverted before the signal is routed to port 3, pin 3.

Logic 0 on P2.3 sets the LIN bus to the LOW state, whereas logic 1 on P2.3 sets the LIN bus to the HIGH state.

PGA450-Q1 RX_pin_conn_lds185.gif Figure 38. LIN Tx and Rx Pins Are Connected to 8051W Port Pins

The reason for routing the Rx pin to P3.2 and P3.3 is to allow the use of 8051W timer 1 to measure the durations of the LIN bus in the high or low state.

7.4 Device Functional Modes

7.4.1 Active Mode

The process of taking a measurement occurs when the device is in active mode. The low-side drivers, analog front-end, and digital data path are all active which allows for an ultrasonic signal to be transmitted and the reflected signal to be received and processed.

The maximum current (VREG not charging) in active mode is 15 mA.

To enter active mode, set the ACTIVE_EN bit in the PWR_MODE register to 1.

7.4.2 Quiet Mode

In quiet mode, the device waits for a command which is given through a digital interface (such as LIN, SCI, or UART). The LNA, ADC, digital data path, and low-side drivers are all off. The VREG regulator can be either enabled or disabled. If the VREG regulator is charging, the maximum current is increased by 100 mA.

The maximum current (VREG not charging) in quiet mode is 7.5 mA.

To enter quiet mode, set the ACTIVE_EN bit in the PWR_MODE register to 0.

7.4.3 RESET

The PGA450-Q1 can also be put into a RESET state where the microcontroller is not active. During this state, SPI is the only digital interface that can be used. The low-side drivers can still be triggered to begin an ultrasonic burst and the analog front-end and digital data path can still store the returned echo signal in the FIFO RAM. However, any processing of the FIFO RAM by the internal microprocessor to determine the location of an object does not occur. The FIFO RAM data can be read over SPI, allowing an external microprocessor to process the data.

While the microcontroller is active, the MICRO RESET test register is the only register accessible through SPI. The device must be put into the RESET state before sending additional SPI commands.

The maximum current (VREG not charging) in the RESET state is 15 mA.

To put the microcontroller in reset, write a 1 to bit 0 of the MICRO RESET (address 0x2F) test register. Transmit the TEST Write SPI command in the following order: 0x16, 0x2F, 0x01.

To bring the microcontroller out of reset, write a 0 to bit 0 of the MICRO RESET (address 0x2F) test register. Transmit the TEST Write SPI command in the following order: 0x16, 0x2F, 0x00.

NOTE

The MICRO RESET (0x2F) register is an internal test register, which is why the field is not listed in the SFR or ESFR register map.

7.5 Programming

7.5.1 SPI Interface

PGA450-Q1 SPI_port_lds185.gif Figure 39. SPI Port in PGA450-Q1

The SPI block is used for communicating with the device during system development. The internal SPI acts as the slave in the communication of the device with an external SPI which is in master mode. To perform the communication, four external pins are necessary:

    SDI: SPI slave-in master-out, serial-input pin
    SDO: SPI slave-out master-in, serial-output pin (three-state output)
    SCLK: SPI clock, which controls the communication
    CS: Chip select

The output data on the SDO pin (for example, CheckByte and read data) changes on the rising edge of SCLK. The input data on SDI is latched on the falling edge of SCLK. The data received during a write access is written to memory on the system clock after the CS pin has gone high.

In the absence of active transmission, the master SPI resets the internal SPI with CS = high. MISO is in the high-impedance state during reset. Master and slave SPI transmit the MSB first.

NOTE

The PGA450-Q1 does not respond to SPI messages unless the 8051W microprocessor is in the reset state. The microprocessor can be put in the reset state by writing an appropriate value to the MICRO RESET test register. The MICRO RESET test register is the ONLY register that is accessible through the SPI when the 8051W processor is not in the reset state.

7.5.1.1 SPI Interface Protocol

The serial peripheral interface (SPI) uses a 1-byte command word and 2 or 3 additional bytes for the complete command.

Table 14 lists the SPI protocol.

Table 14. SPI Protocol Command Word

BIT FUNCTION
15:13 Always 3’b000
12:10 Memory access control:
3’b001: OTP
3’b010: EXTERNAL RAM (FIFO, general-purpose)
3’b011: EEPROM
3’b100: IRAM
3’b101: TEST registers
3’b110: ESFR
3’b111: Development RAM
9 R/W Access:
Write = 1
Read = 0
8 Parity bit: Odd parity on bits 15:9

When accessing memory (IRAM, ESFR, OTP, EEPROM, FIFO RAM, DEV RAM), the internal registers bits 15:13 must all be zero. If these bits are not zero, the SPI command is rejected and the SPI failure bit is set (see CheckByte below).

7.5.1.2 Transfer Width

Table 15 lists how the SPI transfer width (number of bytes) varies depending on whether the SPI is a read or write to the IRAM, ESFR, EEPROM, OTP, or FIFO data access.

Table 15. SPI Protocol Transfer Widths

MEMORY ACCESS MODE REG ACCESS MEMORY ACCESS R/W PARITY BIT TYPE OF OPERATION ADDRESS DATA DATA TOTAL NO.
OF BYTES
Byte #1 (Breakdown) Bytes
Bits 7:5 Bits 4:2 Bit 1 Bit 0 Byte #1 (Hex) Byte #2 Byte #3 Byte #4
Internal RAM write 000 100 1 1 13 8-bit RAM Address 8-bit Write Data — 3
Internal RAM read 000 100 0 0 10 8-bit RAM Address 8-bit Don't Care — 3
ESFR write 000 110 1 0 1A 8-bit ESFR Address 8-bit Write Data — 3
ESFR read 000 110 0 1 19 8-bit ESFR Address 8-bit Don't Care — 3
OTP write 000 001 1 1 07 OTP Address 15:8 OTP Address 7:0 8-bit write data 4
OTP read 000 001 0 0 04 OTP Address 15:8 OTP Address 7:0 8-bit don't care 4
EEPROM cache write 000 011 1 0 0E 8-bit EEPROM Address 8-bit Write Data — 3
EEPROM cache read 000 011 0 1 0D 8-bit EEPROM Address 8-bit Don't Care — 3
External RAM write 000 010 1 1 0B EXTERNAL RAM Address 15:8 EXTERNAL Address 7:0 8-bit write data 4
External RAM read 000 010 0 0 08 EXTERNAL Address 15:8 EXTERNAL Address 7:0 8-bit don't care 3
DEV RAM write 000 111 1 1 1F DEV RAM Address 15:8 DEV RAM Address 7:0 8-bit write data 4
DEV RAM read 000 111 0 0 1C DEV RAM Address 15:8 DEV RAM Address 7:0 8-bit don't care 4
TEST write 000 101 1 0 16 8-bit TEST Address 8-bit Write Data — 3
TEST read 000 101 0 1 15 8-bit TEST Address 8-bit Don't Care — 3

For a SPI transfer to the internal register file, the parity P depends on the address.

For SPI transfers to the memories (IRAM, ESFR, OTP), the read data is available on the next SPI transfer. That is, when reading from a memory location, the user must send a subsequent transfer to get the data back.

PGA450-Q1 SPI_read_res_lds185.gif Figure 40. Response to SPI Read Commands Is Available When the Next Command Is Sent

7.5.1.3 CheckByte

On every SPI transfer, the PGA450-Q1 transmits a CheckByte which is in the 8 most significant bits of the transfer. For example, in a 16-bit transfer, the CheckByte is in bits 15:8 of the received data; similarly, for a 24 bit transfer the CheckByte is in bits 23:16 of the received data. The CheckByte can be used by the SPI master to detect SPI communication errors.

PGA450-Q1 CheckByte_lds185.gif Figure 41. CheckByte Is Transmitted by PGA450-Q1 at the Beginning of Every Response

Table 16 lists the interpretation of each bit in the CheckByte transmitted by the PGA450-Q1.

For a successful SPI transfer, the CheckByte reads 8’h02. Bit 9 of the CheckByte is always set in order to assist debugging in the lab. If the SPI transfer failed for some reason, the most significant bit (15) of the CheckByte is set. The reason for the failure is then described in bits 14:11.

Table 16. SPI Protocol, CheckByte Field

CheckByte BIT ERROR DESCRIPTION
15 (or most significant bit) SPI transfer failure SPI transfer failure
14 Parity error Parity error; command-byte parity incorrect
13 Illegal address Illegal address; bits 15:13 and 12:10 cannot both be active
12 Illegal command Illegal command; memory access bits 12:10 invalid
11 Wrong number of clocks Wrong number clocks; must only receive 16, 24, or 32 clocks
10:8 Always 3’b010 Always 3’b010

7.5.1.4 Examples

Table 17 lists a few examples of SPI transfer:

Table 17. SPI Protocol Examples

COMMAND SPI SLAVE TRANSFER
Read internal register 0 (revision id) ({3’h0, 3’h0, 1’b0, 1’b1}, 8’hXX)
Write 0x80 to internal register 1 (MicroConfig) ({3’h1, 3’h0, 1’b1, 1’b1}, 8’hC8)
Write 0x34 to internal RAM 0x7F ({3’h0, 3’h4, 1’b1, 1’b1}, 8’h7F, 8’h34)
Read from ESFR 0xC0 ({3’h0, 3’h6, 1’b0, 1’b1}, 8’hC0)
Write 0xD9 to OTP 0x1765 ({3’h0, 3’h1, 1’b1, 1’b1}, 8’h17, 8’h65, 8’hD9)
Failed write 0xC8 to internal register 1 (bad parity) ({3’h1, 3’h0, 1’b1, 1’b0}, 8’hC8)
Failed write 0xC8 to internal register 1 (illegal address) ({3’h1, 3’h1, 1’b1, 1’b0}, 8’hC8)
Failed write 0x34 to memory (illegal command) ({3’h0, 3’h7, 1’b1, 1’b1}, 8’h7F, 8’h34)

7.5.2 Diagnostics

7.5.2.1 Power-Block Monitors

The following operating-condition monitors have been implemented on the PGA450-Q1 to ensure reliable and robust performance over the lifetime of the device.

  • VPWR overvoltage (greater than 28 V nominal, 20-µs deglitch time)
  • VPWR level is such that AVDD is undervoltage (less than 6 V nominal, 2-ms deglitch time)
  • AVDD overcurrent (greater than 55 mA nominal, 2-ms deglitch time)
  • RBIAS overcurrent (greater than 63 µA nominal, 2-ms deglitch time)

NOTE

Whenever these monitors sense a violation in the operating conditions, the
microprocessor is held in reset.

A corresponding fault flag is also set in the STATUS1 register.

The fault flags are cleared when the fault condition is removed or when the device is reset.

7.5.2.2 Low-Side Diagnostics

The PGA450-Q1 has diagnostics implemented on the LS driver to protect the LS FET from sinking excessive currents when it is enabled. A fault condition is sensed if both the Vgs voltage and the Vds voltage on the LS FET remain above 2.5 V for the duration of either 1 µs or 2 µs (selectable by setting the LS_FAULT_TIMER_SEL bit in the CONTROL_1 register) during a turnon event. If a fault is sensed, the LS FET is immediately turned off and a corresponding flag is set in the STATUS2 register. The fault is automatically cleared when the LS FET is commanded to turn on in the next cycle.

The LS diagnostics are turned off by default and can be enabled by setting the LS_FAULT_LOGIC_EN bit in the CONTROL_1 register.

Figure 42 shows the schematic of the low-side drive and Figure 43 shows the timing diagram of the low-side diagnostics.

PGA450-Q1 low_side_sch_lds185.gif Figure 42. Low-Side Drive Schematic
PGA450-Q1 ls_fault_timing_lds185.gif
A. Gate is commanded on by LS driver logic. This 0 -> 1 edge enables the LS fault diagnostic on the LS Driver if the LS_FAULT_LOGIC_EN is set.
B. Drain monitor (DRAIN_MON) senses that drain is below 2.5 V for a normal scenario, where as the drain monitor output remains high for the fault scenario.
C. Gate monitor (GATE_MON) senses that gate is above 2.5 V.
D. For the fault scenario, bcause GATE_MON and DRAIN_MON signals have remained high for the selected fault time (1 µs or 2 µs), a fault is sensed and the gate is immediately turned off.
Figure 43. Low-Side Fault Timing

7.5.2.3 Main Oscillator Watchdog

The PGA450-Q1 implements an internal free-running 500-kHz watchdog clock. This watchdog clock is used to monitor the internal 16-MHz main oscillator or the external crystal oscillator. When this frequency is outside this range, an internal reset is generated, which resets the entire digital core; this is equivalent to POR.

The main oscillator frequency fail limits have the following ranges as shown in Figure 44:

  • If the main oscillator frequency is less than 5.4 MHz, the watchdog logic recognizes this as a low-frequency fail and resets the digital core.
  • If the main oscillator frequency lies in the range: 5.4 MHz < Main OSC Freq < 14 MHz, there is a possibility that the watchdog recognizes this as a low-frequency fail and resets the core, but reset is not assured.
  • If the main oscillator frequency lies in the range: 14 MHz < Main Osc Freq < 18 MHz, the main osc watchdog does NOT reset the core, as this is seen as the nominal frequency of operation.
  • If the main oscillator frequency lies in the range 18 MHz < Main Osc Freq < 43 MHz, there is a possibility that the watchdog recognizes this as a high-frequency fail and resets the core, but reset is not assured.
  • If the main oscillator frequency is greater than 43 MHz, the watchdog logic recognizes this as a high-frequency fail and resets the digital core.

PGA450-Q1 main_oscill_lds185.gif Figure 44. Main Oscillator Frequency and the Corresponding PGA450-Q1 Behavior

The main oscillator watchdog can be disabled using the OSC_WD_EN bit in the WD_EN register.

NOTE

A reset because of main oscillator watchdog failure causes an internal digital core reset. All ESFRs revert back to the reset sate.

7.5.2.4 Software Watchdog

The PGA450-Q1 implements a software watchdog. This watchdog must be serviced by software every 250 ms. If the software does not service the watchdog within 250 ms of the last service, then the transducer drive FETs are turned OFF and the 8051W core is reset.

The software services the watchdog using port pin P3.7 as shown in Figure 45. The software services the watchdog by toggling the state of P3.7.

PGA450-Q1 watchdog_sw_lds185.gif Figure 45. Connection Between the 8051W and the Software Watchdog

The software watchdog can be disabled using the SW_WD_EN bit in the WD_EN register. The following lists the behavior of this bit:

  • The SW_WD_EN bit is in the disabled state after power-on reset (POR).
  • If the 8051W is reset through the SPI, then SW_WD_EN is disabled.
  • If SW_WD_EN is enabled and the 8051W is reset because the software watchdog has timed out, then SW_WD_EN remains enabled.

NOTE

A reset of the 8051W does not change the state of the ESFR registers. The ESFR registers continue to retain the state.

7.5.2.5 Internal ASIC TRIM Validity

The PGA450-Q1 has internal ASIC trim values. These trim values are used to fine-tune the operation of various blocks at TI manufacturing EOL.

The PGA450-Q1 checks the validity of these ASIC trim values after power up and before the 8051W reset is deasserted. If the internal trim values are not valid, the TRIM_FAIL bit in the STATUS1 register is set. The 8051W software can be used to check this bit after 8051W reset is deasserted and the software starts execution.

7.5.2.6 FIFO RAM and External SRAM MBIST

The PGA450-Q1 verifies the integrity of FIFO RAM and RAM in the external memory space (that is, all RAM in the external memory) with a RAM MBIST. The RAM MBIST begins immediately after POR is deasserted and takes approximately 5 ms. See Figure 8 for power-up waveforms. The 8051W reset is deasserted while MBIST is ongoing.

MBIST sets the MBIST_DONE flag in STATUS1 upon completion of MBIST. The MBIST_FLAG is set to 1 if RAM MBIST fails.

NOTE

The 8051W microprocessor should not enable the digital datapath, should not access the FIFO RAM, and should not access RAM in the external memory space until the RAM MBIST DONE flag is set.

7.5.2.7 Thermal Shutdown

The PGA450-Q1 also has an overtemperature protection feature implemented. An overtemperature violation causes a total shutdown of the part with the microprocessor held in reset. When the device cools down below the overtemperature threshold, the device initiates a power up again.

7.5.3 8051W Interrupts

The MCU 8051 provides the five standard 8051-compatible legacy interrupts, plus expansion capability for a further nine extended interrupts sourced from external user logic. The standard and extended interrupts each have separate enable-register bits associated with them, allowing software control. The interrupts can also have two levels of priority assigned to them. The interrupts are defined as follows:

    Standard interrupts The five standard interrupts comprise two timer overflow interrupts, an interrupt associated with the built-in serial interface of the core, and two external interrupts (referred to as legacy external interrupts).
    Timer-overflow interrupts The two timer-overflow interrupts, TF0 and TF1, are set whenever their respective timers timer 0 and timer 1, roll over to zero. The states of these interrupts are also stored in the TCON register. The TF0 and TF1 interrupts are automatically cleared by hardware on entry to the corresponding interrupt service routine.

    NOTE

    All events on NINT0 and NINT1, whether level-triggered or edge-triggered, are detected by sampling the relevant interrupt line on the rising edge of SCLK at the end of phase 1 of every machine cycle. Where NINT0/NINT1 is level-triggered, a response is made to the signal being sampled low and, to ensure detection, the external source must hold the line low until the resulting interrupt is generated. (It also must ensure that the request is de-activated before the end of the associated service routine.) Where NINT0 or NINT1 is edge-triggered, the response is made to a transition on the signal from high to low between successive samples. This means that, to ensure detection, NINT0 or NINT1 must have been high for at least two clocks before it goes low and then must be held low for at least two clocks after this transition.
    Serial interrupt The serial interrupts source comprises the logical OR of the two serial interface status bits RI and TI in register SCON. These interrupts are set automatically on receipt or transmission of a data frame. These two bits are not cleared by hardware.
    Legacy external interrupts The two legacy external interrupts, NINT0 and NINT1, are driven from inputs PORT3(2) and PORT3(3), respectively. These interrupts can be either edge- or level-sensitive, depending on settings within the TCON register. Two further TCON register bits, IE0 and IE1, act as interrupt flags. If the external interrupt is set to edge-triggered, the corresponding register bit IE0 or IE1 is set by a falling edge on NINT0 or NINT1 and cleared by hardware on entry to the corresponding interrupt service routine. If the interrupt is set to be level-sensitive, IE0or IE1 reflects the logic level on NINT0 or NINT1. The TCON register is described in the Timer and Counter Control Register (offset = 0x88) [reset = 0] section.
    Extended interrupts Source and acknowledge signals are provided for a further nine interrupts. These interrupts are driven from external user logic, typically a user ESFR. The extended interrupts are input to the core on bits 5 to 13 of input bus XINTR_SRC, whereas acknowledge signals are output from the core on bits 5 to 13 of bus XINTR_ACK. Note: If the timers or the UART are omitted from the design, their corresponding interrupt inputs (plus those of the legacy external interrupts where the timers are omitted) are made available at the core periphery as XINTR_SRC[4:0], along with corresponding XINTR_ACK acknowledge signals, for use as additional extended interrupts.)
    I
    The extended-interrupt lines are sampled on the rising edge of PCLK at the beginning of phase 2 of the last cycle of the current instruction. To ensure detection, the external source must hold the XINTR_SRC line high until the resulting interrupt is generated and must also ensure that the request is deactivated before the end of the associated service routine.
    I
    Any edge-triggering that is required must be taken care of by individual peripherals.

NOTE

For additional information about these five standard interrupts, see the Intel 8-Bit Embedded Controller Handbook in the Hardware Description of the 8051, 8052 and 80C51.)

7.5.3.1 Interrupt Flag Clear

If the legacy external interrupts, NINT0 and NINT1, are edge-triggered, the interrupt flag is cleared on vectoring to the service routine. If these interrupts are level-triggered, the flag is controlled by the external signal. Timer and counter flags are cleared on vectoring to the interrupt service routine, but the serial interrupt flag is not affected by hardware. The serial interrupt flag should be cleared by software. Acknowledge signals are provided for clearing any registers used to source the nine additional interrupts.

7.5.3.2 Priority Levels and Interrupt Vectors

One of two priority levels can be selected for each interrupt. An interrupt of high priority may interrupt the service routine of a low-priority interrupt and, if two interrupts of different priority occur at the same time, the higher-level interrupt is serviced first. An interrupt cannot be interrupted by another interrupt of the same priority level. If two interrupts of the same priority level occur simultaneously, a polling sequence is observed as listed in Table 18:

When an interrupt is serviced, a long call instruction is executed to one of the following locations, according to the source of the interrupt as listed in Table 18.

Table 18. Interrupt Summary

8051W SOURCE PGA450-Q1 SOURCE VECTOR ADDRESS POLLING SEQUENCE FLAG ENABLE PRIORITY CONTROL
External interrupt 0 LIN RX 0x0003 1 (highest) IE0 (TCON.1) EX0 (IE.0) PX0 (IP.0)
Timer and counter interrupt 0 ← 0x000B 2 TF0 (TCON.5) ET0 (IE.1) PT0 (IP.1)
External interrupt 1 LIN ~RX 0x0013 3 IE1 (TCON.3) EX1 (IE.2) PX1 (IP.2)
Timer and counter interrupt 1 ← 0x001B 4 TF1 (TCON.7) ET1 (IE.3) PT1 (IP.3)
Serial port 0 ← 0x0023 5 RI_0 (SCON0.0)TI_0 (SCON0.1) ES0 (IE.4) PS0 (IP.4)
External interrupt 5 LIN PID received 0x002B 6 — EI5 (IE.5) PI5 (IP.5)
External interrupt 6 LIN/SCI DATA received 0x0033 7 — EI6 (IE1.0) PI6 (IP1.0)
External interrupt 7 LIN/SCI data transmit complete 0x003B 8 — EI7 (IE1.1) PI7 (IP1.1)
External interrupt 8 LIN SYNC received 0x0043 9 — EI8 (IE1.2) PI8 (IP1.2)
External interrupt 9 0x004B 10 — EI9 (IE1.3) PI9 (IP1.3)
External interrupt 10 0x0053 11 — EI10 (IE14) P10 (IP1.4)
External interrupt 11 0x005B 12 — EI11 (IE1.5) P11 (IP1.5)
External interrupt 12 0x0063 13 — EI12 (IE1.6) P12 (IP16)
External interrupt 13 0x006B 14 (Lowest) — EI13 (IE1.7) P13 (IP.7)

7.5.3.3 Interrupt Latency

The response time in a single interrupt system is between 3 and 9 machine cycles.

7.5.4 Instructions

The M8051 Warp instruction set is listed in Table 20. The following sections outline some of the supported features.

7.5.4.1 Addressing Modes

The M8051 Warp provides a variety of addressing modes, which are outlined as follows.

7.5.4.1.1 Direct Addressing

In direct addressing, the operand is specified by an 8-bit address field. Only internal data and SFRs can be accessed using this mode.

7.5.4.1.2 Indirect Addressing

In indirect addressing, the operand is specified by an address contained in a register. Two registers (R0 and R1) from the current bank or the data pointer can be used for addressing in this mode. Both internal and external data memory can be indirectly addressed.

7.5.4.1.3 Register Addressing

In register addressing, the operand is specified by the top 3 bits of the opcode, which selects one of the current bank of registers. Four banks of registers are available. The current bank is selected by bits 3 and 4 of the PSW.

7.5.4.1.4 Register Specific Addressing

Some instructions only operate on specific registers which is defined by the opcode. In particular, many accumulator operations and some stack pointer operations are defined in this manner.

7.5.4.1.5 Immediate Data

Instructions which use immediate data are 2 or 3 bytes long, and the immediate operand is stored in program memory as part of the instruction.

7.5.4.1.6 Indexed Addressing

Only program memory can be addressed using indexed addressing. This memory is intended for simple implementation of look-up tables. A 16-bit base register (either the PC or the DPTR) is combined with an offset stored in the accumulator to access data in program memory.

7.5.4.2 Arithmetic Instructions

The M8051 Warp implements ADD, ADDC (add with carry), SUBB (subtract with borrow), INC (increment), and DEC (decrement) functions, which can be used in most addressing modes. There are three accumulator-specific instructions, DA A (decimal adjust A), MUL AB (multiply A by B) and DIV AB (divide A by B).

7.5.4.3 Logical Instructions

The M8051 Warp implements ANL (AND logical), ORL (OR logical), and XRL (exclusive-OR logical) functions, which again can be used in most addressing modes. Seven accumulator-specific instructions are available, CLR A (clear A), CPL A (complement A), RL A (rotate left A), RLC A (rotate left through carry A), RR A (rotate right A), RRC A (rotate right through carry A), and SWAP A (swap nibbles of A).

7.5.4.4 Data Transfers

7.5.4.4.1 Internal Data Memory

Data can be moved from the accumulator to any internal data memory location, from any internal data memory location to the accumulator, and from any internal data memory location to any SFR or other internal data memory location.

7.5.4.4.2 External Data Memory

Data can be moved from the accumulator to or from an external memory location in one of two addressing modes. In 8-bit addressing mode, the external location is addressed by either R0 or R1; in 16-bit addressing mode, the location is addressed by the DPTR.

7.5.4.5 Jump Instructions

7.5.4.5.1 Unconditional Jumps

Four sorts of unconditional jump instructions are available. Short jumps (SJMP) are relative jumps (limited to –128 to 127 bytes), long jumps (LJMP) are absolute 16-bit jumps, and absolute jumps (AJMP) are absolute 11-bit jumps (that is, within a 2K byte memory page). The last type is an indexed jump, JMP @A+DPTR, which jumps to a location contained in the DPTR register, offset by a value stored in the accumulator.

7.5.4.5.2 Subroutine Calls and Returns

Only two sorts of subroutine call are available, ACALL and LCALL, which are absolute and long as previously described. Two return instructions are provided, RET and RETI. The latter is for interrupt service routines.

7.5.4.5.3 Conditional Jumps

Conditional jump instructions all use relative addressing and there fore are limited to the same –128- to 127-byte range as previously described.

7.5.4.6 Boolean Instructions

The bit-addressable registers in both the direct and SFR space can be manipulated using Boolean instructions. Logical functions are available which use the carry flag and an addressable bit as the operands and each addressable bit can be set, cleared, or tested in a jump instruction.

7.5.4.7 Flags

Table 19 lists the instructions that affect the flags generated by the ALU.

Table 19. Flag Summary

INSTRUCTION FLAG INSTRUCTION FLAG
C OV AC C OV AC
ADD ? ? ? CLRC 0
ADDC ? ? ? CPLC ?
SUBB ? ? ? ANL C, bit ?
MUL 0 ? ANL C, /bit ?
DIV 0 ? ORL C, bit ?
DA ? ORL C, /bit ?
RRC ? MOV C, bit ?
RLC ? CJNE ?
SETB C 1

In Table 19, a 0 indicates that the flag is always cleared, a 1 indicates that the flag is always set, and a question mark (?) indicates that the state of the flag depends on the result of the operation. The flag specified as blank means that the state is unknown.

7.5.4.8 Instruction Table

Instructions are either 1, 2, or 3 bytes long as listed in the BYTES column of Table 20. Each instruction requires either 1, 2 or 4 machine cycles to execute as listed in Table 20. One machine cycle comprises 2 CCLK clock cycles.

Table 20. Instructions

MNEMONIC DESCRIPTION BYTES CYCLES HEX CODE
ARITHMETIC
ADD A,Rn Add register to A 1 1 28–2F
ADD A,dir Add direct byte to A 2 1 25
ADD A,@Ri Add indirect memory to A 1 1 26–27
ADD A,#data Add immediate to A 2 1 24
ADDC A,Rn Add register to A with carry 1 1 38–3F
ADDC A,dir Add direct byte to A with carry 2 1 35
ADDC A,@Ri Add indirect memory to A with carry 1 1 36–37
ADDC A,#data Add immediate to A with carry 2 1 34
SUBB A,Rn Subtract register from A with borrow 1 1 98–9F
SUBB A,dir Subtract direct byte from A with borrow 2 1 95
SUBB A,@Ri Subtract indirect memory from A with borrow 1 1 96–97
SUBB A,#data Subtract immediate from A with borrow
INC A Increment A 1 1 4
INC Rn Increment register 1 1 08–0F
INC dir Increment direct byte 2 1 5
INC @Ri Increment indirect memory 1 1 06-07
DEC A Decrement A 1 1 14
DEC Rn Decrement register 1 1 18–1F
DEC dir Decrement direct byte 2 1 15
DEC @Ri Decrement indirect memory 1 1 16–17
INC DPTR Increment data pointer 1 2 A3
MUL AB Multiply A by B 1 4 A4
DIV AB Divide A by B 1 4 84
DA A Decimal Adjust A 1 1 D4
LOGICAL
ANL A,Rn AND register to A 1 1 58–5F
ANL A,dir AND direct byte to A 2 1 55
ANL A,@Ri AND indirect memory to A 1 1 56–57
ANL A,#data AND immediate to A 2 1 54
ANL dir,A AND A to direct byte 2 1 52
ANL dir,#data AND immediate to direct byte 3 2 53
ORL A,Rn OR register to A 1 1 48–4F
ORL A,dir OR direct byte to A 2 1 45
ORL A,@Ri OR indirect memory to A 1 1 46–47
ORL A,#data OR immediate to A 2 1 44
ORL dir,A OR A to direct byte 2 1 42
ORL dir,#data OR immediate to direct byte 3 2 43
XRL A,Rn Exclusive-OR register to A 1 1 68–6F
XRL A,dir Exclusive-OR direct byte to A 2 1 65
XRL A, @Ri Exclusive-OR indirect memory to A 1 1 66–67
XRL A,#data Exclusive-OR immediate to A 2 1 64
XRL dir,A Exclusive-OR A to direct byte 2 1 62
XRL dir,#data Exclusive-OR immediate to direct byte 3 2 63
CLR A Clear A 1 1 E4
CPL A Complement A 1 1 F4
SWAP A Swap Nibbles of A 1 1 C4
RL A Rotate A left 1 1 23
RLC A Rotate A left through carry 1 1 33
RR A Rotate A right 1 1 3
RRC A Rotate A right through carry 1 1 13
DATA TRANSFER
MOV A,Rn Move register to A 1 1 E8–EF
MOV A,dir Move direct byte to A 2 1 E5
MOV A,@Ri Move indirect memory to A 1 1 E6–E7
MOV A,#data Move immediate to A 2 1 74
MOV Rn,A Move A to register 1 1 F8–FF
MOV Rn,dir Move direct byte to register 2 2 A8–AF
MOV Rn,#data Move immediate to register 2 1 78–7F
MOV dir,A Move A to direct byte 2 1 F5
MOV dir,Rn Move register to direct byte 2 2 88–8F
MOV dir,dir Move direct byte to direct byte 3 2 85
MOV dir,@Ri Move indirect memory to direct byte 2 2 86–87
MOV dir,#data Move immediate to direct byte 3 2 75
MOV @Ri,A Move A to indirect memory 1 1 F6–F7
MOV @Ri,dir Move direct byte to indirect memory 2 2 A6–A7
MOV @Ri,#data Move immediate to indirect memory 2 1 76–77
MOV DPTR,#data Move immediate to data pointer 3 2 90
MOVC A,@A+DPTR Move code byte relative DPTR to A 1 2 93
MOVC A,@A+PC Move code byte relative PC to A 1 2 83
MOVX A,@Ri Move external data(A8) to A 1 2 E2–E3
MOVX A,@DPTR Move external data(A16) to A 1 2 E0
MOVX @Ri,A Move A to external data(A8) 1 2 F2–F3
MOVX @DPTR,A Move A to external data(A16) 1 2 F0
PUSH dir Push direct byte onto stack 2 2 C0
POP dir Pop direct byte from stack 2 2 D0
XCH A,Rn Exchange A and register 1 1 C8–CF
XCH A,dir Exchange A and direct byte 2 1 C5
XCH A,@Ri Exchange A and indirect memory 1 1 C6–C7
XCHD A,@Ri Exchange A and indirect memory nibble 1 1 D6–D7
BOOLEAN
CLR C Clear carry 1 1 C3
CLR bit Clear direct bit 2 1 C2
SETB C Set carry 1 1 D3
SETB bit Set direct bit 2 1 D2
CPL C Complement carry 1 1 B3
CPL bit Complement direct bit 2 1 B2
ANL C,bit AND direct bit to carry 2 2 82
ANL C,/bit AND direct bit inverse to carry 2 2 B0
ORL C,bit OR direct bit to carry 2 2 72
ORL C,/bit OR direct bit inverse to carry 2 2 A0
MOV C,bit Move direct bit to carry 2 1 A2
MOV bit,C Move carry to direct bit 2 2 92
BRANCHING
ACALL addr 11 Absolute jump to subroutine 2 2 11→F1
LCALL addr 16 Long jump to subroutine 3 2 12
RET Return from subroutine 1 2 22
RETI Return from interrupt 1 2 32
AJMP addr 11 Absolute jump unconditional 2 2 01→E1
LJMP addr 16 Long jump unconditional 3 2 2
SJMP rel Short jump (relative address) 2 2 80
JC rel Jump on carry = 1 2 2 40
JNC rel Jump on carry = 0 2 2 50
JB bit,rel Jump on direct bit = 1 3 2 20
JNB bit,rel Jump on direct bit = 0 3 2 30
JBC bit,rel Jump on direct bit = 1 and clear 3 2 10
JMP @A+DPTR Jump indirect relative DPTR 1 2 73
JZ rel Jump on accumulator = 0 2 2 60
JNZ rel Jump on accumulator ≠ 0 2 2 70
CJNE A,dir,rel Compare A,direct jne relative 3 2 B5
CJNE A,#d,rel Compare A,immediate jne relative 3 2 B4
CJNE Rn,#d,rel Compare register, immediate jne relative 3 2 B8–BF
CJNE @Ri,#d,rel Compare indirect, immediate jne relative 3 2 B6–B7
DJNZ Rn,rel Decrement register, jnz relative 2 2 D8–DF
DJNZ dir,rel Decrement direct byte, jnz relative 3 2 D5
MISCELLANEOUS
NOP No operation 1 1 0

In Table 20, an entry such as E8–EF indicates a continuous block of hex opcodes used for 8 different registers, the register numbers of which are defined by the lowest three bits of the corresponding code. Non-continuous blocks of codes, shown as 11→F1 (for example), are used for absolute jumps and calls, with the top 3 bits of the code being used to store the top three bits of the destination address.

The CJNE instructions use the abbreviation #d for immediate data; other instructions use #data.

7.5.5 8051W Port Usage

The 8051W has four I/O ports. lists the port usage in the PGA450-Q1 device.

Table 21. 8051W I/O Port Usage in PGA450-Q1

PORT BIT USAGE IN PGA450-Q1
Port 0 0 OTP security
1 OTP security
2 OTP security
3 OTP security
4 OTP security
5 OTP security
6 OTP security
7 OTP security
Port 1 0
1
2
3
4
5
6
7
Port 2 0 Low side A
1 Low side B
2
3 LIN Tx
4
5
6
7
Port 3 0 UART RxD
1 UART TxD
2 LIN Rx/external interrupt input 0, active-low
3 ~LIN Rx/external interrupt input 1, active-low
4 GPIO1/Timer 0 external input
5 GPIO2/Timer 1 external input
6
7 Software watchdog

7.6 Register Maps

The memory block consists of SRAM, OTP, and EEPROM. The SRAM is used as storage for volatile software variables during program execution. The OTP consists of the program code and the EEPROM consists of calibrations.

PGA450-Q1 memory_map_lds185.gif Figure 46. PGA450 Memory Map

Table 22. SFR Memory Map

Address (hex) Description D6 D5 D4 D3 D2 D1 D0 R/W POWER ON Value
80 Port 0 (P0) P0[6] P0[5] P0[4] P0[3] P0[2] P0[1] P0[0] R/W 0xFF
81 Stack Pointer SP[6] SP[5] SP[4] SP[3] SP[2] SP[1] SP[0] R/W 0
82 Data Pointer Low Byte DPTR[6] DPTR[5] DPTR[4] DPTR[3] DPTR[2] DPTR[1] DPTR[0] R/W 0
83 Data Pointer High Byte DPTR[14] DPTR[13] DPTR[12] DPTR[11] DPTR[10] DPTR[9] DPTR[8] R/W 0
87 Power control Register GF1 GF0 PD IDL R/W 0
88 Timer / Counter Control TR1 TF0 TR0 IE1 IT1 IE0 IT0 R/W 0
89 Timer / Counter Mode CNT1 M1 (1) M0 (1) GATE0 CNT0 M1 (0) M0 (0) R/W 0
8A Timer / Counter Data (TL0) TL0[6] TL0[5] TL0[4] TL0[3] TL0[2] TL0[1] TL0[0] R/W 0
8B Timer / Counter Data (TL1) TL1[6] TL1[5] TL1[4] TL1[3] TL1[2] TL1[1] TL1[0] R/W 0
8C Timer / Counter Data (TH0) TH0[6] TH0[5] TH0[4] TH0[3] TH0[2] TH0[1] TH0[0] R/W 0
8D Timer / Counter Data (TH1) TH1[6] TH1[5] TH1[4] TH1[3] TH1[2] TH1[1] TH1[0] R/W 0
90 Port 1 (P1) P1[6] P1[5] P1[4] P1[3] P1[2] P1[1] P1[0] R/W 0xFF
98 UART Control (SCON) SM1 SM2 REN TB8 RB8 TI RI R/W 0
99 UART Data (SBUF) SBUF[6] SBUF[5] SBUF[4] SBUF[3] SBUF[2] SBUF[1] SBUF[0] R/W 0
A0 Port 2 (P2) P2[6] P2[5] P2[4] P2[3] P2[2] P2[1] P2[0] R/W 0xFF
A8 Interrupt Enable Register 0 EI5 ES ET1 EX1 ET0 EX0 R/W 0
B0 Port 3 (P3) P3[6] P3[5] P3[4] P3[3] P3[2] P3[1] P3[0] R/W 0xFF
B8 Interrupt Priority Register 0 PI5 PS PT1 PX1 PT0 PX0 R/W 0
D0 Program Status Word AC F0 RS1 RS0 OV F1 P R/W 0
E0 Accumulator ACC[6] ACC[5] ACC[4] ACC[3] ACC[2] ACC[1] ACC[0] R/W 0
E8 Interrupt Enable Register 1 EI12 EI11 EI10 EI9 EI8 EI7 EI6 R/W 0
F0 Register (B) B[6] B[5] B[4] B[3] B[2] B[1] B[0] R/W 0
F8 Interrupt Priority Register 1 PI12 PI11 PI10 PI9 PI8 PI7 PI6 R/W 0

Table 23. ESFR Memory Map

Address (hex) D7 D6 D5 D4 D3 D2 D1 D0 R/W Power Up Description (Programmable Regs)
92 BPF_B1[15] BPF_B114] BPF_B1[13] BPF_B1[12] BPF_B1[11] BPF_B1[10] BPF_B1[9] BPF_B1[8] R/W 0 BPF_B1_MSB
93 BPF_B1[7] BPF_B1[6] BPF_B1[5] BPF_B1[4] BPF_B1[3] BPF_B1[2] BPF_B1[1] BPF_B1[0] R/W 0 BPF_B1_LSB
94 BPF_A2[15] BPF_A2[14] BPF_A2[13] BPF_A2[12] BPF_A2[11] BPF_A2[10] BPF_A2[9] BPF_A2[8] R/W 0 BPF_A2_MSB
95 BPF_A2[7] BPF_A2[6] BPF_A2[5] BPF_A2[4] BPF_A2[3] BPF_A2[2] BPF_A2[1] BPF_A2[0] R/W 0 BPF_A2_LSB
96 BPF_A3[15] BPF_A3[14] BPF_A3[13] BPF_A3[12] BPF_A3[11] BPF_A3[10] BPF_A3[9] BPF_A3[8] R/W 0 BPF_A3_MSB
97 BPF_A3[7] BPF_A3[6] BPF_A3[5] BPF_A3[4] BPF_A3[3] BPF_A3[2] BPF_A3[1] BPF_A3[0] R/W 0 BPF_A3_LSB
A1 LPF_B1[14] LPF_B1[13] LPF_B1[12] LPF_B1[11] LPF_B1[10] LPF_B1[9] LPF_B1[8] R/W 0 LPF_B1_MSB
A2 LPF_B1[7] LPF_B1[6] LPF_B1[5] LPF_B1[4] LPF_B1[3] LPF_B1[2] LPF_B1[1] LPF_B1[0] R/W 0 LPF_B1_LSB
A3 LPF_A2[14] LPF_A2[13] LPF_A2[12] LPF_A2[11] LPF_A2[10] LPF_A2[9] LPF_A2[8] R/W 0 LPF_A2_MSB
A4 LPF_A2[7] LPF_A2[6] LPF_A2[5] LPF_A2[4] LPF_A2[3] LPF_A2[2] LPF_A2[1] LPF_A2[0] R/W 0 LPF_A2_LSB
A5 DS5 DS4 DS3 DS2 DS1 DS0 R/W 0 DOWNSAMPLE
A6 ONA[10] ONA[9] ONA[8] R/W 0 ONA_MSB
A7 ONA[7] ONA[6] ONA[5] ONA[4] ONA[3] ONA[2] ONA[1] ONA[0] R/W 0 ONA_LSB
A9 OFFA[10] OFFA[9] OFFA[8] R/W 0 OFFA_MSB
AA OFFA[7] OFFA[6] OFFA[5] OFFA[4] OFFA[3] OFFA[2] OFFA[1] OFFA[0] R/W 0 OFFA_LSB
AB ONB[10] ONB[9] ONB[8] R/W 0 ONB_MSB
AC ONB[7] ONB[6] ONB[5] ONB[4] ONB[3] ONB[2] ONB[1] ONB[0] R/W 0 ONB_LSB
AD OFFB[10] OFFB[9] OFFB[8] R/W 0 OFFB_MSB
AE OFFB[7] OFFB[6] OFFB[5] OFFB[4] OFFB[3] OFFB[2] OFFB[1] OFFB[0] R/W 0 OFFB_LSB
AF PCA5 PCA4 PCA3 PCA2 PCA1 PCA0 R/W 0 PULSE_CNTA
B1 PCB5 PCB4 PCB3 PCB2 PCB1 PCB0 R/W 0 PULSE_CNTB
B2 DT7 DT6 DT5 DT4 DT3 DT2 DT1 DT0 R/W 0 DEADTIME
B3 BMODE2 BMODE1 BMODE0 R/W 0 BURST_MODE
B4 TS7 TS6 TS5 TS4 TS3 TS2 TS1 TS0 R 0 TEMP_SENS
B5 SD7 SD6 SD5 SD4 SD3 SD2 SD1 SD0 R/W 0 SAT_DEGLITCH
B6 ST7 ST6 ST5 ST4 ST3 ST2 ST1 ST0 R 0 SAT_TIME
B7 LS_FAULT_LOGIC_EN LS_FAULT_TIMER_SEL LNA_GAIN1 LNA_GAIN0 SAT_SEL1 SAT_SEL0 R/W 0 CONTROL_1
B9 BT7 BT6 BT5 BT4 BT3 BT2 BT1 BT0 R/W 0 BLANKING_TIMER
BA FRT[15] FRT[14] FRT[13] FRT[12] FRT[11] FRT[10] FRT[9] FRT[8] R 0 FRT_MSB
BB FRT[7] FRT[6] FRT[5] FRT[4] FRT[3] FRT[2] FRT[1] FRT[0] R 0 FRT_LSB
BC MICRO_LIN_TX UARTTX_CONFIG GPIO2_CONFIG2 GPIO2_CONFIG1 GPIO2_CONFIG0 GPIO1_CONFIG2 GPIO1_CONFIG1 GPIO1_CONFIG0 R/W 0 GPIO_CTRL
BD CLK_SEL1 CLK_SEL0 R/W 0 CLK_SEL
BE SW_WD_EN OSC_WD_EN R/W 0 WD_EN
BF LIN_SCI R/W 0 LIN_SCI
C0 RELOAD WRITE/EE_STATUS R/W 0 EE_CTRL
C1 TRIM_FAIL MBIST_DONE MBIST_FAIL VPWR_OV AVDD_UV AVDD_OC RBIAS_OC R N/A STATUS1
C2 WD_TO_OSC LSB_FAULT LSA_FAULT WD_TO_SW SAT_DONE VREG_READY R N/A STATUS2
C3 VREG_EN ACTIVE_EN R/W 0 PWR_MODE
C4 FIFO_ADC SCI_TX_EN FIFO_PEAKDET R/W 0 DP_SCI_CTRL
C5 NROLLOVER FMODE1 FMODE0 R/W 0 FIFO_CTRL
C8 CAP_FR_TIMER ECHO_EN SAT_EN BURST_B_EN BURST_EN R N/A EN_CTRL
C9 RX_DATA1[7] RX_DATA1[6] RX_DATA1[5] RX_DATA1[4] RX_DATA1[3] RX_DATA1[2] RX_DATA1[1] RX_DATA1[0] R N/A RX_DATA1
CA RX_DATA2[7] RX_DATA2[6] RX_DATA2[5] RX_DATA2[4] RX_DATA2[3] RX_DATA2[2] RX_DATA2[1] RX_DATA2[0] R N/A RX_DATA2
CB RX_DATA3[7] RX_DATA3[6] RX_DATA3[5] RX_DATA3[4] RX_DATA3[3] RX_DATA3[2] RX_DATA3[1] RX_DATA3[0] R N/A RX_DATA3
CC RX_DATA4[7] RX_DATA4[6] RX_DATA4[5] RX_DATA4[4] RX_DATA4[3] RX_DATA4[2] RX_DATA4[1] RX_DATA4[0] R N/A RX_DATA4
CD RX_DATA5[7] RX_DATA5[6] RX_DATA5[5] RX_DATA5[4] RX_DATA5[3] RX_DATA5[2] RX_DATA5[1] RX_DATA5[0] R N/A RX_DATA5
CE RX_DATA6[7] RX_DATA6[6] RX_DATA6[5] RX_DATA6[4] RX_DATA6[3] RX_DATA6[2] RX_DATA6[1] RX_DATA6[0] R N/A RX_DATA6
CF RX_DATA7[7] RX_DATA7[6] RX_DATA7[5] RX_DATA7[4] RX_DATA7[3] RX_DATA7[2] RX_DATA7[1] RX_DATA7[0] R N/A RX_DATA7
D1 RX_DATA8[7] RX_DATA8[6] RX_DATA8[5] RX_DATA8[4] RX_DATA8[3] RX_DATA8[2] RX_DATA8[1] RX_DATA8[0] R N/A RX_DATA8
D2 PID7 PID6 PID5 PID4 PID3 PID2 PID1 PID0 R N/A LIN_PID
D3 TX_DATA1[7] TX_DATA1[6] TX_DATA1[5] TX_DATA1[4] TX_DATA1[3] TX_DATA1[2] TX_DATA1[1] TX_DATA1[0] R/W N/A TX_DATA1
D4 TX_DATA2[7] TX_DATA2[6] TX_DATA2[5] TX_DATA2[4] TX_DATA2[3] TX_DATA2[2] TX_DATA2[1] TX_DATA2[0] R/W N/A TX_DATA2
D5 TX_DATA3[7] TX_DATA3[6] TX_DATA3[5] TX_DATA3[4] TX_DATA3[3] TX_DATA3[2] TX_DATA3[1] TX_DATA3[0] R/W N/A TX_DATA3
D6 TX_DATA4[7] TX_DATA4[6] TX_DATA4[5] TX_DATA4[4] TX_DATA4[3] TX_DATA4[2] TX_DATA4[1] TX_DATA4[0] R/W N/A TX_DATA4
D7 TX_DATA5[7] TX_DATA5[6] TX_DATA5[5] TX_DATA5[4] TX_DATA5[3] TX_DATA5[2] TX_DATA5[1] TX_DATA5[0] R/W N/A TX_DATA5
D8 TX_DATA6[7] TX_DATA6[6] TX_DATA6[5] TX_DATA6[4] TX_DATA6[3] TX_DATA6[2] TX_DATA6[1] TX_DATA6[0] R/W N/A TX_DATA6
D9 TX_DATA7[7] TX_DATA7[6] TX_DATA7[5] TX_DATA7[4] TX_DATA7[3] TX_DATA7[2] TX_DATA7[1] TX_DATA7[0] R/W N/A TX_DATA7
DA TX_DATA8[7] TX_DATA8[6] TX_DATA8[5] TX_DATA8[4] TX_DATA8[3] TX_DATA8[2] TX_DATA8[1] TX_DATA8[0] R/W N/A TX_DATA8
DB CNT3 CNT2 CNT1 CNT0 R/W N/A DATA_CNT
DC BIT_TOL CS_METHOD CLR_ERR INTERBYTE_SPC HOLD IGNORE_DIAG R/W 0x40 LIN_CFG
DD RX_TX R/W N/A LIN_CTRL
DE BREAK_DEL SYNC_LONG SYNC_SHORT STOP_BIT_SHORT STOP_BIT_VAL PARITY CHECKSUM R N/A LIN_STATUS
DF FIFO_PTR[9] FIFO_PTR[8] R/W N/A FIFO_POINTER_MSB
E1 FIFO_PTR[7] FIFO_PTR[6] FIFO_PTR[5] FIFO_PTR[4] FIFO_PTR[3] FIFO_PTR[2] FIFO_PTR[1] FIFO_PTR[0] R N/A FIFO_POINTER_LSB
E2 VREG_SEL3 VREG_SEL2 VREG_SEL1 VREG_SEL0 R/W 0 VREG_SEL
E3 SC[15] SC[14] SC[13] SC[12] SC[11] SC[10] SC[9] SC[8] R/W 0 SYNC_COUNT_MSB
E4 SC[7] SC[6] SC[5] SC[4] SC[3] SC[2] SC[1] SC[0] R/W 0 SYNC_COUNT_LSB
E5 TS_DAC_MODE TS_DAC_EN R/W 0 TEMP_DAC_CTRL
E6 OVR OS5 OS4 OS3 OS2 OS1 OS0 R/W 0 OSC_SYNC_CTRL
E9 AMUX3 AMUX2 AMUX1 AMUX0 R/W 0 ANALOG_MUX
EA DMUX4 DMUX3 DMUX2 DMUX1 DMUX0 R/W 0 DIGITAL_MUX

7.6.1 SFR Registers

7.6.1.1 I/O Ports (P0, P1, P2, P3) Registers

P0, P1, P2, and P3 are latches used to drive the 32 quasi-bidirectional I/O lines. On reset, these registers are all set to the value FF hex, which is input mode. Table 21 lists the port usage in the PGA450-Q1 device.

7.6.1.1.1 I/O Port 3 Register (offset = 0xB0) [reset = 0xFF]

Bit addressable

Figure 47. I/O Port 3 (P3) Register
7 6 5 4 3 2 1 0
P3[7] P3[6] P3[5] P3[4] P3[3] P3[2] P3[1] P3[0]
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 W-1 R-1

Table 24. P3 Register Field Descriptions

Bit Field Type Reset Description
7 P3[7] R/W 1
6 P3[6] R/W 1
5 P3[5] R/W 1 This bit has an alternate function as a T1 input
4 P3[4] R/W 1 This bit has an alternate function as a T0 input
3 P3[3] R/W 1 This bit has an alternate function as an NINT1 input
2 P3[2] R/W 1 This bit has an alternate function as an NINT0 input
1 P3[1] W 1 This bit has an alternate function as a TXD output. When functioning as a TXD output, this bit serial transmits data from the UART and transmit clock in UART mode 0.
0 P3[0] R 1 This bit has an alternate function as a RXD input. When functioning as a RXD inupt, this bit serial receives data to the UART.

7.6.1.1.2 I/O Port 2 Register (offset = 0xA0) [reset = 0xFF]

Figure 48. I/O Port 2 (P2)
7 6 5 4 3 2 1 0
P2[7] P2[6] P2[5] P2[4] P2[3] P2[2] P2[1] P2[0]
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1

Table 25. P2 Register Field Descriptions

Bit Field Type Reset Description
7-0 P2[7:0] R/W 1

7.6.1.1.3 I/O Port 1 Register (offset = 0x90) [reset = 0xFF]

Figure 49. I/O Port 1 (P1) Register
7 6 5 4 3 2 1 0
P1[7] P1[6] P1[5] P1[4] P1[3] P1[2] P1[1] P1[0]
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1

Table 26. P1 Register Field Descriptions

Bit Field Type Reset Description
7-0 P1[7:0] R/W 1

7.6.1.1.4 I/O Port 0 (P0) (offset = 0x80) [reset = 0xFF]

Figure 50. I/O Port 0 (P0) Register
7 6 5 4 3 2 1 0
P0[7] P0[6] P0[5] P0[4] P0[3] P0[2] P0[1] P0[0]
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1

Table 27. P0 Register Field Descriptions

Bit Field Type Reset Description
7-0 P0[7:0] R/W 1

7.6.1.2 Stack Pointer Register (offset = 0x81) [reset = 0]

Not bit-addressable

The SP register contains the stack pointer. The stack pointer is used to load the program counter into internal data memory during LCALL and ACALL instructions and is used to retrieve the program counter from memory during RET and RETI instructions. Data can also be saved on or retrieved from the stack using PUSH and POP instructions. Instructions that use the stack automatically pre-increment or post-decrement the stack pointer so that the stack pointer always points to the last byte written to the stack, that is, the top of the stack. On reset the stack pointer is set to 07h. The user must ensure that the location of the stack in internal data memory does not interfere with other data stored therein.

Another use of the scratchpad area is for the programmer stack. This area is selected using the stack pointer (SP, SFR 81h). Whenever a call or interrupt is invoked, the return address is placed on the stack. The stack is also available to the user for variables, and so forth, because the stack can be moved and there is no fixed location within the RAM designated as stack. The stack pointer defaults to 07h on reset, and the user can then move it as needed. The SP points to the last used value. Therefore, the next value placed on the stack is put at SP + 1. Each PUSH or CALL increments the SP by the appropriate value, and each POP or RET decrements it.

Figure 51. Stack Pointer (SP) Register
7 6 5 4 3 2 1 0
SP[7] SP[6] SP[5] SP[4] SP[3] SP[2] SP[1] SP[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-1 R/W-1 R/W-1

Table 28. SP Register Field Descriptions

Bit Field Type Reset Description
7-0 SP[7:0] R/W 0

7.6.1.3 Data Pointer Registers

Not bit-addressable.

The data pointer (DPTR) is a 16-bit register that may be accessed through the two SFR locations, data-pointer high byte (DPH) and data-pointer low byte (DPL). Two true 16-bit operations are allowed on the data pointer, load immediate and increment. The data pointer is used to form 16-bit addresses for external data memory accesses (MOVX), for program byte moves (MOVC) and for indirect program jumps (JMP @A+DPTR). On reset, the data pointer is set to 0000h.

7.6.1.3.1 Data Pointer Register (offset = 0x82) [reset = 0]

This is the 8 LSB of the data pointer.

Figure 52. Data Pointer (DPL) Register
7 6 5 4 3 2 1 0
DPTR[7] DPTR[6] DPTR[5] DPTR[4] DPTR[3] DPTR[2] DPTR[1] DPTR[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 29. DPL Register Field Descriptions

Bit Field Type Reset Description
7-0 DPTR[7:0] R/W 0

7.6.1.3.2 Data Pointer Register (offset = 0x83) [reset = 0]

This is the 8 MSB of the data pointer.

Figure 53. Data Pointer (DPH) Register
7 6 5 4 3 2 1 0
DPTR[15] DPTR[14] DPTR[13] DPTR[12] DPTR[11] DPTR[10] DPTR[9] DPTR[8]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 30. DPH Register Field Descriptions

Bit Field Type Reset Description
7-0 DPTR[15:8] R/W 0

7.6.1.4 Power Control Register (offset = 0x87) [reset = 0]

Not bit-addressable.

Figure 54. Power Control (PCON) Register
7 6 5 4 3 2 1 0
SMOD — GF[1:0] PD IDL
R/W-0 R-0 R/W-0 R/W-0 R/W-0

Table 31. PCON Register Field Descriptions

Bit Field Type Reset Description
7 SMOD R/W 0 Double baud rate bit. For use, see Table 40.
6-4 R 0
3-2 GF[1:0] R/W 0 General-purpose flag bit
1 PD R/W 0 Power-down bit. If 1, power-down mode is entered.
0 IDL R/W 0 Idle bit. If 1, idle mode is entered.

7.6.1.5 Timer and Counter Control Register (offset = 0x88) [reset = 0]

Bit Addressable.

Two 16-bit timer and counters are provided. The TCON and TMOD bits are used to set the mode of operation and to control the running and interrupt generation of the timer and counters. The timer andcounter values are stored in two pairs of 8-bit registers (TL0, TH0, TL1, and TH1).

Figure 55. Timer and Counter Control (TCON) Register
7 6 5 4 3 2 1 0
TF1 TR1 TF0 TR0 IE1 IT1 IE0 IT0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 32. TCON Register Field Descriptions

Bit Field Type Reset Description
7 TF1 R/W 0 Timer 1 overflow flag. Set by hardware when timer and counter 1 overflows. Cleared by hardware when the processor calls the interrupt service routine.
6 TR1 R/W 0 Timer 1 run control. If 1, timer runs; if 0, timer is halted.
5 TF0 R/W 0 Timer 0 overflow flag. Set by hardware when timer and counter 0 overflows. Cleared by hardware when the processor calls the interrupt service routine.
4 TR0 R/W 0 Timer 0 run control. If 1, timer runs; if 0, timer is halted.
3 IE1 R/W 0 External Interrupt 1 edge flag. Set by hardware when an external interrupt 1 edge is detected.
2 IT1 R/W 0 External Interrupt 1 control bit. If 1, external interrupt 1 is edge-triggered; if 0, external interrupt 1 is level-triggered.
1 IE0 R/W 0 External Interrupt 0 edge flag. Set by hardware when an external interrupt 0 edge is detected.
0 IT0 R/W 0 External Interrupt 0 control bit. If 1, external interrupt 0 is edge-triggered; if 0, external interrupt 0 is level-triggered

7.6.1.6 Timer and Counter Mode Register (offset = 0x89) [reset = 0]

Not Bit Addressable.

Figure 56. Timer and Counter Mode (TMOD) Register
7 6 5 4 3 2 1 0
GATE1 CNT1 M1 (1) M0 (1) GATE0 CNT0 M1 (0) M0 (0)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 33. TMOD Register Field Descriptions

Bit Field Type Reset Description
7 GATE1 R/W 0 Timer 1 gate flag. When TR1 is set and GATE1= 1, timer and counter 1 only runs if the NINT1 pin is 1 (hardware control). When GATE1 = 0, timer and counter 1 only runs if TR1 = 1 (software control).
6 CNT1 R/W 0 Timer and counter-1 selector. If 0, input is from the internal system clock; if 1, input is from the T1 pin.
5 M1 (1) R/W 0 Timer 1 mode-control bit M1.
4 M0 (1) R/W 0 Timer 1 mode-control bit M0.
3 GATE0 R/W 0 Timer 0 gate flag. When TR0 is set and GATE0 = 1, timer and counter 0 only runs if NINT0 pin is 1 (hardware control). When GATE0 = 0, timer and counter 0 only runs if TR0 = 1 (software control).
2 CNT0 R/W 0 Timer and counter 0 selector. If 0, input is from the internal system clock; if 1, input is from the T0 pin.
1 M1 (0) R/W 0 Timer 0 mode-control bit M1
0 M0 (0) R/W 0 Timer 0 mode-control bit M0

Table 34. Timer Mode Control Bits

M1 M0 Operating Mode
0 0 13-bit timer and counter (M8048-compatible mode)
0 1 16-bit timer and counter
1 0 8-bit auto-reload timer and counter
1 1 Timer 0 is split into two halves. TL0 is an 8-bit timer and counter controlled by the standard timer 0 control bits. TH0 is an 8-bit timer and counter controlled by the standard timer 1 control bits. TH1 and TL1 are held (timer 1 is stopped).

7.6.1.7 Timer and Counter Data Registers (TL0, TL1, TH0, TH1)

Not bit-addressable.

TL0 and TH0 are the low and high bytes, respectively, of timer and counter 0. TL1 and TH1 are the low and high bytes, respectively, of timer and counter 1. In mode 2, the TL register is an 8-bit counter, and TH stores the reload value. On reset, all timer and counter registers are 00h.

The timer-clock resolution is 8 MHz.

7.6.1.7.1 TL0 Register (offset = 0x8A) [reset = 0]

Figure 57. TL0 Register
7 6 5 4 3 2 1 0
TL0[7] TL0[6] TL0[5] TL0[4] TL0[3] TL0[2] TL0[1] TL0[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 35. TL0 Register Field Descriptions

Bit Field Type Reset Description
7-0 TL0[7:0] R/W 0

7.6.1.7.2 TL1 Register (offset = 0x8B) [reset = 0]

Figure 58. TL1 Register
7 6 5 4 3 2 1 0
TL1[7] TL1[6] TL1[5] TL1[4] TL1[3] TL1[2] TL1[1] TL1[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 36. TL1 Register Field Descriptions

Bit Field Type Reset Description
7-0 TL1[7:0] R/W 0

7.6.1.7.3 TH0 Register (offset = 0x8C) [reset = 0]

Figure 59. TH0 Register
7 6 5 4 3 2 1 0
TH0[7] TH0[6] TH0[5] TH0[4] TH0[3] TH0[2] TH0[1] TH0[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 37. TH0 Register Field Descriptions

Bit Field Type Reset Description
7-0 TH0[7:0] R/W 0

7.6.1.7.4 TH1 Register (offset = 0x8D) [reset = 0]

Figure 60. TH1 Register
7 6 5 4 3 2 1 0
TH1[7] TH1[6] TH1[5] TH1[4] TH1[3] TH1[2] TH1[1] TH1[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 38. TH1 Register Field Descriptions

Bit Field Type Reset Description
7-0 TH1[7:0] R/W 0

7.6.1.8 UART Control Register (offset = 0x98) [reset = 0]

Bit-addressable

The UART uses two SFRs: SCON and SBUF. SCON is the control register and SBUF is the data register. Data is written to SBUF for transmission and SBUF is read to obtain received data. The received-data and transmitted-data registers are independent.

SM2 enables multi-processor communication over a single serial line and modifies the foregoing as listed in Table 40. In modes 2 and 3, if SM2 is set then the receive interrupt is not generated if the received 9th data bit is 0. In mode 1, the receive interrupt is not generated unless a valid stop bit is received. In mode 0, SM2 should be 0.

Figure 61. UART Control (SCON) Register
7 6 5 4 3 2 1 0
SM0 SM1 SM2 REN TB8 RB8 TI RI
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 39. SCON Register Field Descriptions

Bit Field Type Reset Description
7 SM0 R/W 0 UART mode specifier
6 SM1 R/W 0 UART mode specifier
5 SM2 R/W 0 UART mode specifier
4 REN R/W 0 If 1, enables reception; if 0, disables reception
3 TB8 R/W 0 In modes 2 and 3, this is the 9th data bit sent.
2 RB8 R/W 0 In modes 2 and 3, this is the 9th data bit received. In mode 1, if SM2 = 0, this is the stop bit received. In mode 0, this bit is not used.
1 TI R/W 0 Transmit interrupt flag. This is set by hardware at the end of the 8th bit in mode 0, or at the beginning of the stop bit in other modes. Must be cleared by software.
0 RI R/W 0 Receive interrupt flag. This is set by hardware at the end of the 8th bit in mode 0, or at the half-point of the stop bit in other modes. Must be cleared by software.

Table 40. Mode Control Bit Operation(1)

Mode SM0 SM1 Operating Mode Baud Rate
Mode 0 0 0 Mode 0: 8-bit shift register. ftimer_clk /2 Baud rate = ftimer_clk / 2
Mode 1 0 1 Mode 1: 8 bit UART. Baud rate = (SMOD+1) × ftimer_clk / (32 × (256 – TH1))
Mode 2 1 0 Mode 2: 9 bit UART. Baud rate = (SMOD + 1) × ftimer_clk / 64
Mode 3 1 1 Mode 3: 9 bit UART. Baud rate = (SMOD + 1) × ftimer_clk / (32 × (256 – TH1))
(1) ftimer_clk is the frequency of the TIMER_CLK input (8 MHz)

7.6.1.9 UART Data Register (offset = 0x99) [reset = 0]

Not bit-addressable

This register is used for both transmit and receive data. Transmit data is written to this location and receive data is read from this location, but the two paths are independent.

Figure 62. UART Data (SBUF) Register
7 6 5 4 3 2 1 0
SBUF[7] SBUF[6] SBUF[5] SBUF[4] SBUF[3] SBUF[2] SBUF[1] SBUF[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 41. SBUF Register Field Descriptions

Bit Field Type Reset Description
7-0 SBUF[7:0] R/W 0

7.6.1.10 Interrupt Enable Register 0 (offset = 0xA8) [reset = 0]

Bit-addressable.

The two interrupt enable registers (IE0 and IE1) control the 14 available interrupts. Five of these interrupts are standard 8051-compatible legacy interrupts. The other nine are specific to the PGA450-Q1 device. More information on interrupts can be found in the 8051W Interrupts section.

For each bit in this register, a 1 enables the corresponding interrupt, and a 0 disables it.

Figure 63. Interrupt Enable Register 0 (IE0)
7 6 5 4 3 2 1 0
EA — EI5 ES ET1 EX1 ET0 EX0
R/W-0 R-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 42. IE0 Register Field Descriptions

Bit Field Type Reset Description
7 EA R/W 0 Enable or disable all interrupt bits.
6 R 0
5 EI5 R/W 0 Enable external Interrupt 5, the LIN PID received interrupt.
4 ES R/W 0 Enable serial port interrupt.
3 ET1 R/W 0 Enable timer 1 overflow interrupt.
2 EX1 R/W 0 Enable external interrupt 1, the NINT1 interrupt.
1 ET0 R/W 0 Enable timer 0 overflow interrupt.
0 EX0 R/W 0 Enable external interrupt 0, the NINT0 interrupt.

7.6.1.11 Interrupt Enable Register 1 (offset = 0xE8) [reset = 0]

Bit-addressable.

See the 8051W Interrupts section for more information on available interrupts.

For each bit in this register, a 1 enables the corresponding interrupt, and a 0 disables it.

Figure 64. Interrupt Enable Register 1 (IE1)
7 6 5 4 3 2 1 0
EI13 EI12 EI11 EI10 EI9 EI8 EI7 EI6
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 43. IE1 Register Field Descriptions

Bit Field Type Reset Description
7 EI13 R/W 0 Enable external interrupt 13.
6 EI12 R/W 0 Enable external interrupt 12.
5 EI11 R/W 0 Enable external interrupt 11.
4 EI10 R/W 0 Enable external interrupt 10.
3 EI9 R/W 0 Enable external interrupt 9.
2 EI8 R/W 0 Enable external interrupt 8, the LIN SYNC received interrupt.
1 EI7 R/W 0 Enable external interrupt 7, the LIN/SCI data transmit complete interrupt.
0 EI6 R/W 0 Enable external interrupt 6, the LIN/SCI data received interrupt.

7.6.1.12 Interrupt Priority Register 0 (offset = 0xB8) [reset = 0]

Bit-addressable.

For each bit in this register, a setting of 1 selects high priority for the corresponding interrupt, and a setting of 0 selects low priority. While an interrupt is being serviced, it may only be interrupted by a higher priority interrupt. See the 8051W Interrupts section for more information on available interrupts.

Figure 65. Interrupt Priority Register 0 (IP0)
7 6 5 4 3 2 1 0
— PI5 PS PT1 PX1 PT0 PX0
R-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 44. IP0 Register Field Descriptions

Bit Field Type Reset Description
7-6 R 0
5 PI5 R/W 0 Select priority for external interrupt 5, the LIN PID received interrupt.
4 PS R/W 0 Select priority for serial port interrupt.
3 PT1 R/W 0 Select priority for timer 1 overflow interrupt.
2 PX1 R/W 0 Select priority for external interrupt 1, the NINT1 interrupt.
1 PT0 R/W 0 Select priority for timer 0 overflow interrupt.
0 PX0 R/W 0 Select priority for external interrupt 0, the NINT0 interrupt.

7.6.1.13 Interrupt Priority Register 1 (offset = 0xF8) [reset = 0]

Bit-addressable

For each bit in this register, a setting of 1 selects high priority for the corresponding interrupt, and a setting 0 selects low priority. While an interrupt is being serviced, it may only be interrupted by a higher priority interrupt. See the 8051W Interrupts section for more information on available interrupts.

Figure 66. Interrupt Priority Register 1 (IP1)
7 6 5 4 3 2 1 0
PI13 PI12 PI11 PI10 PI9 PI8 PI7 PI6
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 45. IP1 Register Field Descriptions

Bit Field Type Reset Description
7 PI13 R/W 0 Select priority for external interrupt 13.
6 PI12 R/W 0 Select priority for external interrupt 12.
5 PI11 R/W 0 Select priority for external interrupt 11.
4 PI10 R/W 0 Select priority for external interrupt 10.
3 PI9 R/W 0 Select priority for external interrupt 9.
2 PI8 R/W 0 Select priority for external interrupt 8, the LIN SYNC received interrupt.
1 PI7 R/W 0 Select priority for external interrupt 7, the LIN/SCI data transmit complete interrupt.
0 PI6 R/W 0 Select priority for external interrupt 6, the LIN/SCI data received interrupt.

7.6.1.14 Program Status Word Register (offset = 0xD0) [reset = 0]

Bit-addressable

This register contains status information resulting from CPU and ALU operation.

Figure 67. Program Status Word (PSW) Register
7 6 5 4 3 2 1 0
CY AC F0 RS1 RS0 OV F1 P
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 46. PSW Register Field Descriptions

Bit Field Type Reset Description
7 CY R/W 0 ALU carry flag
6 AC R/W 0 ALU auxiliary carry flag
5 F0 R/W 0 General-purpose user-definable flag
4 RS1 R/W 0 Register bank-select bit 1
3 RS0 R/W 0 Register bank-select bit 0
2 OV R/W 0 ALU overflow flag
1 F1 R/W 0 User-definable flag
0 P R/W 0 Parity flag. Set each instruction cycle to indicate odd or even parity in the accumulator.

Table 47. Register Bank-Select Bit Operation

RS1 RS0 Register Bank Select
0 0 RB0: registers from 0x00–0x07
0 1 RB1: Registers from 0x08–0x0F
1 0 RB2: Registers from 0x10–0x17
1 1 RB3: Registers from 0x18–0x1F

7.6.1.15 Accumulator Register (offset = 0xE0) [reset = 0]

Bit-addressable

This register provides one of the operands for most ALU operations which is denoted as A in the instruction table.

Figure 68. Accumulator (ACC) Register
7 6 5 4 3 2 1 0
ACC[7] ACC[6] ACC[5] ACC[4] ACC[3] ACC[2] ACC[1] ACC[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 48. ACC Register Field Descriptions

Bit Field Type Reset Description
7-0 ACC[7:0] R/W 0

7.6.1.16 B Register (offset = 0xF0) [reset = 0]

Bit-addressable

This register provides the second operand for multiply or divide instructions which is denoted as B in the instruction table. Otherwise, the register may be used as a scratch pad register.

Figure 69. B Register
7 6 5 4 3 2 1 0
B[7] B[6] B[5] B[4] B[3] B[2] B[1] B[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 49. B Register Field Descriptions

Bit Field Type Reset Description
7-0 B[7:0] R/W 0

7.6.2 ESFR Registers

7.6.2.1 Bandpass Filter Coefficient B1 (BPF_B1) Register

Not bit-addressable.

These registers store the B1 coefficient value for the 2nd order Butterworth bandpass IIR filter. The B1 coefficient helps set the bandwidth of the bandpass filter, which can be programmed from 4 kHz to 7kHz. The specific values to program into these registers for each bandwidth are listed in Table 7.

7.6.2.1.1 Bandpass Filter B1 MSB Register (offset = 0x92) [reset = 0]

Figure 70. Bandpass Filter B1 MSB (BPF_B1_MSB) Register
7 6 5 4 3 2 1 0
BPF_B1[15] BPF_B1[14] BPF_B1[13] BPF_B1[12] BPF_B1[11] BPF_B1[10] BPF_B1[9] BPF_B1[8]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 50. BPF_B1_MSB Register Field Descriptions

Bit Field Type Reset Description
7-0 BPF_B1[15:8] R/W 0

7.6.2.1.2 Bandpass Filter B1 LSB Register (offset = 0x93) [reset = 0]

Figure 71. Bandpass Filter B1 LSB (BPF_B1_LSB) Register
7 6 5 4 3 2 1 0
BPF_B1[7] BPF_B1[6] BPF_B1[5] BPF_B1[4] BPF_B1[3] BPF_B1[2] BPF_B1[1] BPF_B1[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 51. BPF_B1_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 BPF_B1[7:0] R/W 0

7.6.2.2 Bandpass Filter Coefficient A2 (BPF_A2) Registers

Not bit-addressable

These registers store the A2 coefficient value for the 2nd order Butterworth bandpass IIR filter. The A2 coefficient helps set the center frequency of the bandpass filter, which can be programmed from 40 kHz to 70 kHz. The specific values to program into these registers for each center frequency are listed in Table 8.

7.6.2.2.1 Bandpass Filter Coefficient A2 MSB Register (offset = 0x94) [reset = 0]

Figure 72. Bandpass Filter Coefficient A2 MSB (BPF_A2_MSB) Register
7 6 5 4 3 2 1 0
BPF_A2[15] BPF_A2[14] BPF_A2[13] BPF_A2[12] BPF_A2[11] BPF_A2[10] BPF_A2[9] BPF_A2[8]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 52. BPF_A2_MSB Register Field Descriptions

Bit Field Type Reset Description
7-0 BPF_A2[15:8] R/W 0

7.6.2.2.2 Bandpass Filter Coefficient A2 LSB Register (offset = 0x95) [reset = 0]

Figure 73. Bandpass Filter Coefficient A2 LSB (BPF_A2_LSB) Register
7 6 5 4 3 2 1 0
BPF_A2[7] BPF_A2[6] BPF_A2[5] BPF_A2[4] BPF_A2[3] BPF_A2[2] BPF_A2[1] BPF_A2[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 53. BPF_A2_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 BPF_A2[7:0] R/W 0

7.6.2.3 Band-Pass Filter Coefficient A3 (BPF_A3) Register

Not bit-addressable

These registers store the A3 coefficient value for the 2nd order Butterworth bandpass IIR filter. The A3 coefficient helps set the bandwidth of the bandpass filter, which can be programmed from 4 kHz to 7kHz. The specific values to program into these registers for each bandwidth are listed in Table 7.

7.6.2.3.1 Band-Pass Filter Coefficient A3 MSB Register (offset = 0x96) [reset = 0]

Figure 74. Band-Pass Filter Coefficient A3 MSB (BPF_A3_MSB) Register
7 6 5 4 3 2 1 0
BPF_A3[15] BPF_A3[14] BPF_A3[13] BPF_A3[12] BPF_A3[11] BPF_A3[10] BPF_A3[9] BPF_A3[8]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 54. BPF_A3_MSB Register Field Descriptions

Bit Field Type Reset Description
7-0 BPF_A3[15:8] R/W 0

7.6.2.3.2 Band-Pass Filter Coefficient A3 LSB Register (offset = 0x97) [reset = 0]

Figure 75. Band-Pass Filter Coefficient A3 LSB (BPF_A3_LSB) Register
7 6 5 4 3 2 1 0
BPF_A3[7] BPF_A3[6] BPF_A3[5] BPF_A3[4] BPF_A3[3] BPF_A3[2] BPF_A3[1] BPF_A3[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 55. BPF_A3_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 BPF_A3[7:0] R/W 0

7.6.2.4 Low-Pass Filter Coefficient B1 (LPF_B1) Registers

Not bit-addressable

These registers store the B1 coefficient value for the 1st order Butterworth low-pass IIR filter. The low-pass filter can be programmed with a cut-off frequency from 0.5 to 4 kHz. The specific values to program into these registers for each cut-off frequency are listed in Table 9.

7.6.2.4.1 Low-Pass Filter Coefficient B1 MSB Register (offset = 0xA1) [reset = 0]

Figure 76. Low-Pass Filter Coefficient B1 MSB (LPF_B1_MSB) Register
7 6 5 4 3 2 1 0
— LPF_B1[14] LPF_B1[13] LPF_B1[12] LPF_B1[11] LPF_B1[10] LPF_B1[9] LPF_B1[8]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 56. LPF_B1_MSB Register Field Descriptions

Bit Field Type Reset Description
7 R/W 0
6-0 LPF_B1[14:8] R/W 0

7.6.2.4.2 Low-Pass Filter Coefficient B1 LSB Register (offset = 0xA2) [reset = 0]

Figure 77. Low-Pass Filter Coefficient B1 LSB (LPF_B1_LSB) Register
7 6 5 4 3 2 1 0
LPF_B1[7] LPF_B1[6] LPF_B1[5] LPF_B1[4] LPF_B1[3] LPF_B1[2] LPF_B1[1] LPF_B1[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 57. LPF_B1_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 LPF_B1[7:0] R/W 0

7.6.2.5 Low-Pass Filter Coefficient A2 (LPF_A2) Registers

Not bit-addressable

These registers store the A2 coefficient value for the 1st order Butterworth low-pass IIR filter. The low-pass filter can be programmed with a cut-off frequency from 0.5 to 4 kHz. The specific values to program into these registers for each cut-off frequency are listed in Table 9.

7.6.2.5.1 Low-Pass Filter Coefficient A2 MSB Register (offset = 0xA3) [reset = 0]

Figure 78. Low-Pass Filter Coefficient A2 MSB (LPF_A2_MSB) Register
7 6 5 4 3 2 1 0
— LPF_A2[14] LPF_A2[13] LPF_A2[12] LPF_A2[11] LPF_A2[10] LPF_A2[9] LPF_A2[8]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 58. LPF_A2_MSB Register Field Descriptions

Bit Field Type Reset Description
7 R/W 0
6-0 LPF_A2[14:8] R/W 0

7.6.2.5.2 Low-Pass Filter Coefficient A2 LSB Register (offset = 0xA4) [reset = 0]

Figure 79. Low-Pass Filter Coefficient A2 LSB (LPF_A2_LSB) Register
7 6 5 4 3 2 1 0
LPF_A2[7] LPF_A2[6] LPF_A2[5] LPF_A2[4] LPF_A2[3] LPF_A2[2] LPF_A2[1] LPF_A2[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 59. LPF_A2_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 LPF_A2[7:0] R/W 0

7.6.2.6 Downsample Register (offset = 0xA5) [reset = 0]

Not bit-addressable.

This register sets the downsample rate in the datapath. If the low-pass filter is needed, then the downsampling rate must be set between 25 and 50. If the low-pass filter is not needed, then the DOWNSAMPLE register must be set between 1 and 63.

Figure 80. Downsample (DOWNSAMPLE) Register
7 6 5 4 3 2 1 0
– DS5 DS4 DS3 DS2 DS1 DS0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 60. DOWNSAMPLE Register Field Descriptions

Bit Field Type Reset Description
7-6 R/W 0
5 DS5 R/W 0
4 DS4 R/W 0
3 DS3 R/W 0
2 DS2 R/W 0
1 DS1 R/W 0
0 DS0 R/W 0

7.6.2.7 BURST ON A Duration (ON_A) Registers

Not bit-addressable

The ON_A register sets the duration that OUTA is held high during one burst. To generate a square wave of a particular frequency (fburst):

Equation 5. ON_A = dec2hex(FOSC / fburst / 2)

The resolution is 62.5 ns.

7.6.2.7.1 BURST ON A Duration MSB Register (offset = 0xA6) [reset = 0]

Figure 81. BURST ON A Duration MSB (ONA_MSB) Register
7 6 5 4 3 2 1 0
— ONA[10] ONA[9] ONA[8]
R/W-0 R/W-0 R/W-0 R/W-0

Table 61. ONA_MSB Register Field Descriptions

Bit Field Type Reset Description
7-3 R/W 0
2-0 ONA[10:8] R/W 0

7.6.2.7.2 BURST ON A Duration LSB Register (offset = 0xA7) [reset = 0]

Figure 82. BURST ON A Duration LSB (ONA_LSB) Register
7 6 5 4 3 2 1 0
ONA[7] ONA[6] ONA[5] ONA[4] ONA[3] ONA[2] ONA[1] ONA[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 62. ONA_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 ONA[7:0] R/W 0

7.6.2.8 BURST OFFA Duration (OFF_A) Register

Not bit-addressable

The OFF_A register sets the duration that OUTA is held low during one bust. To generate a square wave of a particular frequency, set OFF_A = ON_A. The resolution is 62.5 ns.

7.6.2.8.1 BURST OFFA Duration MSB Register (offset = 0xA9) [reset = 0]

Figure 83. BURST OFFA Duration MSB (OFFA_MSB) Register
7 6 5 4 3 2 1 0
— OFFA[10] OFFA[9] OFFA[8]
R/W-0 R/W-0 R/W-0 R/W-0

Table 63. OFFA_MSB Register Field Descriptions

Bit Field Type Reset Description
7-3 R/W 0
2-0 OFFA[10:8] R/W 0

7.6.2.8.2 BURST OFFA Duration LSB Register (offset = 0xAA) [reset = 0]

Figure 84. BURST OFFA Duration LSB (OFFA_LSB) Register
7 6 5 4 3 2 1 0
OFFA[7] OFFA[6] OFFA[5] OFFA[4] OFFA[3] OFFA[2] OFFA[1] OFFA[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 64. OFFA_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 OFFA[7:0] R/W 0

7.6.2.9 BURST ON B Duration (ON_B) Registers

Not bit-addressable

The ON_B register sets the duration that OUTB is held high during one burst. To generate a square wave of a particular frequency (fburst):

Equation 6. ON_B = dec2hex(FOSC / fburst / 2)

The resolution is 62.5 ns.

7.6.2.9.1 BURST ON B Duration MSB Register (offset = 0xAB) [reset = 0]

Figure 85. BURST ON B Duration MSB (ONB_MSB) Register
7 6 5 4 3 2 1 0
— ONB[10] ONB[9] ONB[8]
R/W-0 R/W-0 R/W-0 R/W-0

Table 65. ONB_MSB Register Field Descriptions

Bit Field Type Reset Description
7-3 R/W 0
2-0 ONB[10:8] R/W 0

7.6.2.9.2 BURST ON B Duration LSB Register (offset = 0xAC) [reset = 0]

Figure 86. BURST ON B Duration LSB (ONB_LSB) Register
7 6 5 4 3 2 1 0
ONB[7] ONB[6] ONB[5] ONB[4] ONB[3] ONB[2] ONB[1] ONB[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 66. ONB_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 ONB[7:0] R/W 0

7.6.2.10 BURST OFF B Duration (OFF_B) Register

Not bit-addressable

The OFF_B register sets the duration that OUTB is held low during one bust. To generate a square wave of a particular frequency, set OFF_B = ON_B. The resolution is 62.5 ns.

7.6.2.10.1 BURST OFF B Duration MSB Register (offset = 0xAD) [reset = 0]

Figure 87. BURST OFF B Duration MSB (OFFB_MSB) Register
7 6 5 4 3 2 1 0
— OFFB[10] OFFB[9] OFFB[8]
R/W-0 R/W-0 R/W-0 R/W-0

Table 67. OFFB_MSB Register Field Descriptions

Bit Field Type Reset Description
7-3 R/W 0
2-0 OFFB[10:8] R/W 0

7.6.2.10.2 BURST OFF B Duration LSB Register (offset = 0xAE) [reset = 0]

Figure 88. BURST OFF B Duration LSB (OFFB_LSB) Register
7 6 5 4 3 2 1 0
OFFB[7] OFFB[6] OFFB[5] OFFB[4] OFFB[3] OFFB[2] OFFB[1] OFFB[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 68. OFFB_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 OFFB[7:0] R/W 0

7.6.2.11 Pulse Count A Register (offset = 0xAF) [reset = 0]

Not bit-addressable

The PULSE_CNTA register sets the number of pulses that occur on OUTA when a burst is initiated. The number of pulses can be set from 0 to 63.

Figure 89. Pulse Count A (PULSE_CNTA) Register
7 6 5 4 3 2 1 0
— PC5 PCA4 PCA3 PCA2 PCA1 PCA0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 69. PULSE_CNTA Register Field Descriptions

Bit Field Type Reset Description
7-6 R/W 0
5 PC5 R/W 0
4 PCA4 R/W 0
3 PCA3 R/W 0
2 PCA2 R/W 0
1 PCA1 R/W 0
0 PCA0 R/W 0

7.6.2.12 Pulse Count B Register (offset = 0xB1) [reset = 0]

Not bit-addressable

The PULSE_CNTB register sets the number of pulses that occur on OUTB when a burst is initiated. The number of pulses can be set from 0 to 63.

Figure 90. Pulse Count B (PULSE_CNTB) Register
7 6 5 4 3 2 1 0
— PCB5 PCB4 PCB3 PCB2 PCB1 PCB0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 70. PULSE_CNTB Register Field Descriptions

Bit Field Type Reset Description
7-6 R/W 0
5 PCB5 R/W 0
4 PCB4 R/W 0
3 PCB3 R/W 0
2 PCB2 R/W 0
1 PCB1 R/W 0
0 PCB0 R/W 0

7.6.2.13 Deadtime Register (offset = 0xB2) [reset = 0]

Not bit-addressable

The deadtime is the time both OUTA and OUTB are held low before one or the other turns on. This time is shaved off of the end of the time set in the ON_A and ON_B registers.

Equation 7. DEADTIME = FOSC × tdeadtime

The resolution is 62.5 ns .

Figure 91. Deadtime (DEADTIME) Register
7 6 5 4 3 2 1 0
DT7 DT6 DT5 DT4 DT3 DT2 DT1 DT0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 71. DEADTIME Register Field Descriptions

Bit Field Type Reset Description
7 DT7 R/W 0
6 DT6 R/W 0
5 DT5 R/W 0
4 DT4 R/W 0
3 DT3 R/W 0
2 DT2 R/W 0
1 DT1 R/W 0
0 DT0 R/W 0

7.6.2.14 Burst Mode Register (offset = 0xB3) [reset = 0]

Not bit-addressable

The BURST_MODE register selects from five possible burst configurations. See Table 4 for additional detail.

Figure 92. Burst Mode (BURST_MODE) Register
7 6 5 4 3 2 1 0
— BMODE2 BMODE1 BMODE0
R/W-0 R/W-0 R/W-0 R/W-0

Table 72. BURST_MODE Register Field Descriptions

Bit Field Type Reset Description
7-3 R/W 0
2 BMODE2 R/W 0 See Table 73.
1 BMODE1 R/W 0 See Table 73.
0 BMODE0 R/W 0 See Table 73.

Table 73. Burst Mode Bit Configurations

BMODE2 BMODE1 BMODE0 BURST MODE DESCRIPTION
0 0 0 Push-pull mode
0 0 1 Single-ended on OUTA, micro control on OUTB
0 1 0 Single-ended on OUTB, micro control on OUTA
0 1 1 Single-ended on OUTA, single-ended on OUTB
1 0 0 Micro on OUTA, micro on OUTB
1 0 1 For TI use only
1 1 0 Illegal
1 1 1 Illegal

7.6.2.15 Temperature Sensor Register (offset = 0xB4) [reset = 0]

Not bit-addressable

Figure 93. Temperature Sensor (TEMP_SENS) Register
7 6 5 4 3 2 1 0
TS7 TS6 TS5 TS4 TS3 TS2 TS1 TS0
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 74. TEMP_SENS Register Field Descriptions

Bit Field Type Reset Description
7 TS7 R 0
6 TS6 R 0
5 TS5 R 0
4 TS4 R 0
3 TS3 R 0
2 TS2 R 0
1 TS1 R 0
0 TS0 R 0

7.6.2.16 Saturation Deglitch Time Register (offset = 0xB5) [reset = 0]

Not bit-addressable

The saturation deglitch timer begins when the voltage envelope at the LIM pin drops below a value set in the SAT_CTRL register. When the deglitch timer is finished, the SAT_DONE bit in the STATUS2 register is set to 1, then the time because SAT_EN was set to 1 is captured into the SAT_TIME register. Further details about this process can be found in the Transducer Saturation Time section.

Equation 8. SAT_DEGLITCH = tdeglitch / 2 µs
Figure 94. Saturation Deglitch Time (SAT_DEGLITCH) Register
7 6 5 4 3 2 1 0
SD7 SD6 SD5 SD4 SD3 SD2 SD1 SD0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 75. SAT_DEGLITCH Register Field Descriptions

Bit Field Type Reset Description
7 SD7 R/W 0
6 SD6 R/W 0
5 SD5 R/W 0
4 SD4 R/W 0
3 SD3 R/W 0
2 SD2 R/W 0
1 SD1 R/W 0
0 SD0 R/W 0

7.6.2.17 Saturation Time Capture Register (offset = 0xB6) [reset = 0]

Not bit-addressable

The saturation timer starts when SAT_EN is set to 1 (coincident with the start of a burst). The value of the timer is captured into the SAT_TIME register when the saturation deglitch timer reaches its programmed value (set in the SAT_DELGLITCH register). The saturation deglitch timer does not begin until after the voltage envelope at the LIM pin drops below the value programmed by the SAT_CTRL register.

Equation 9. tsat = SAT_TIME × 16 µs
Figure 95. Saturation Time Capture (SAT_TIME) Register
7 6 5 4 3 2 1 0
ST7 ST6 ST5 ST4 ST3 ST2 ST1 ST0
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 76. SAT_TIME Register Field Descriptions

Bit Field Type Reset Description
7 ST7 R 0
6 ST6 R 0
5 ST5 R 0
4 ST4 R 0
3 ST3 R 0
2 ST2 R 0
1 ST1 R 0
0 ST0 R 0

7.6.2.18 Control 1 Register (offset = 0xB7) [reset = 0]

Not bit-addressable

The SAT_SEL0 and SAT_SEL1 bits set the threshold level for the voltage envelope at the LIM pin. When the envelope at the LIM pin drops below the threshold, the saturation deglitch timer starts.

The LNA_GAIN0 and LNA_GAIN1 bits configure the gain of the LNA as shown in Table 78.

LS_FAULT_LOGIC_EN enables the low-side FET diagnostics. A fault is detected if both the VGS and VDS voltages on the LS FET remain above 2.5 V for either 1 µs or 2 µs (selectable through the LS_FAULT_TIMER_SEL bit). See the Diagnostics section for additional information.

Figure 96. Control 1 (CONTROL_1) Register
7 6 5 4 3 2 1 0
— LS_FAULT_LOGIC_EN LS_FAULT_TIMER_SEL LNA_GAIN1 LNA_GAIN0 SAT_SEL1 SAT_SEL0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 77. CONTROL_1 Register Field Descriptions

Bit Field Type Reset Description
7-6 R/W 0
5 LS_FAULT_LOGIC_EN R/W 0 0: Low-side fault-monitoring deglitch time is 2 µs.
1: Low-side fault-monitoring deglitch time is 1 µs
4 LS_FAULT_TIMER_SEL R/W 0 0: Low-side fault monitoring is disabled.
1: Low-side fault monitoring is enabled.
3 LNA_GAIN1 R/W 0 See Table 79.
2 LNA_GAIN0 R/W 0 See Table 79.
1 SAT_SEL1 R/W 0 See Table 78.
0 SAT_SEL0 R/W 0 See Table 78.

Table 78. SAT_SELx Bit Configuration

Bit SAT_SEL1 SAT_SEL0 Nominal Saturation Threshold
SAT_SEL0 0 0 200 mV
0 1 300 mV
SAT_SEL1 1 0 400 mV
1 1 600 mV

Table 79. LNA_GAINx Bit Configuration

Bit LNA_GAIN1 LNA_GAIN0 Nominal Gain Value
BIT2: LNA_GAIN0 0 0 1750 V/V (63.52 dB)
0 1 930 V/V (59.08 dB)
BIT3: LNA_GAIN1 1 0 517V/V (53.98 dB)
1 1 104 V/V (40.00 dB)

7.6.2.19 Blanking Timer Register (offset = 0xB9) [reset = 0]

Not bit-addressable

The blanking time is how long after echo processing is enabled before the FIFO starts filling up. Echo processing is enabled when ECHO_EN = 1, which is when the blanking timer starts. Typically this is set concurrently with the start of a burst. See the Datapath Activation and Blanking Timer section for additional information.

Equation 10. BLANKING_TIMER = tblanking / 16 µs
Figure 97. Blanking Timer (BLANKING_TIMER) Register
7 6 5 4 3 2 1 0
BT7 BT6 BT5 BT4 BT3 BT2 BT1 BT0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 80. BLANKING_TIMER Register Field Descriptions

Bit Field Type Reset Description
7 BT7 R/W 0
6 BT6 R/W 0
5 BT5 R/W 0
4 BT4 R/W 0
3 BT3 R/W 0
2 BT2 R/W 0
1 BT1 R/W 0
0 BT0 R/W 0

7.6.2.20 Free Running Timer (FRT) Registers

Not bit-addressable

The FRT register is a shadow of the free running timer. The current value of the free running timer is copied into the FRT register when a 1 is written to the CAP_FR_TMR bit in the EN_CTRL register. The resolution of the register is 1 µs. See the Free-Running Timer section for additional information.

7.6.2.20.1 Free Running Timer MSB Registers (offset = 0xBA) [reset = 0]

Figure 98. Free Running Timer MSB (FRT_MSB) Registers
7 6 5 4 3 2 1 0
FRT[15] FRT[14] FRT[13] FRT[12] FRT[11] FRT[10] FRT[9] FRT[8]
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 81. FRT_MSB Register Field Descriptions

Bit Field Type Reset Description
7-0 FRT[15:8] R 0

7.6.2.20.2 Free Running Timer LSB Registers (offset = 0xBB) [reset = 0]

Figure 99. Free Running Timer LSB (FRT_LSB) Registers
7 6 5 4 3 2 1 0
FRT[7] FRT[6] FRT[5] FRT[4] FRT[3] FRT[2] FRT[1] FRT[0]
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 82. FRT_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 FRT[7:0] R 0

7.6.2.21 GPIO Control Register (offset = 0xBC) [reset = 0]

Not bit-addressable

The two GPIOs and TX pin can be configured in strong or weak pullup mode. The MICRO_LIN_TX bit controls the MUX that determines whether the LIN TX signal is controlled by P2.3 in the 8051W or the embedded LIN slave or buffered SCI protocol. See Figure 39.

Figure 100. GPIO Control (GPIO_CTRL) Register
7 6 5 4 3 2 1 0
MICRO_LIN_TX UARTTX_CONFIG GPIO2_CONFIG2 GPIO2_CONFIG1 GPIO2_CONFIG0 GPIO1_CONFIG2 GPIO1_CONFIG1 GPIO1_CONFIG0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 83. GPIO_CTRL Register Field Descriptions

Bit Field Type Reset Description
7 MICRO_LIN_TX R/W 0 0: 8051W port I/O drives TX pin in weak pullup mode
1: 8051W port I/O drives TX pin in strong pullup mode
6 UARTTX_CONFIG R/W 0 0: LIN/SCI peripheral drives LIN transceiver
1: 8051W port I/O drives LIN transceiver
5 GPIO2_CONFIG2 R/W 0 See Table 84.
4 GPIO2_CONFIG1 R/W 0 See Table 84.
3 GPIO2_CONFIG0 R/W 0 See Table 84.
2 GPIO1_CONFIG2 R/W 0 See Table 85.
1 GPIO1_CONFIG1 R/W 0 See Table 85.
0 GPIO1_CONFIG0 R/W 0 See Table 85.

Table 84. GPIO2_CONFIGx Bit Configuration

Bit GPIO2_CONFIG2 GPIO2_CONFIG1 GPIO2_CONFIG0 GPIO2 Mode
GPIO2_CONFIG0
GPIO2_CONFIG1
GPIO2_CONFIG2 		0 X X 8051W port I/O drives GPIO2 pin in weak pullup mode
1 1 X 8051W port I/O drives GPIO2 in strong pullup mode

Table 85. GPIO1_CONFIGx Bit Configuration

Bit GPIO1_CONFIG2 GPIO1_CONFIG1 GPIO1_CONFIG0 GPIO1 Mode
GPIO1_CONFIG0
GPIO1_CONFIG1
GPIO1_CONFIG2 		0 X X 8051W port I/O drives GPIO1 pin in weak pullup mode
1 1 X 8051W port I/O Drives GPIO1 in strong pullup mode
1 0 1 Reserved, do not use

7.6.2.22 Clock Select Register (offset = 0xBD) [reset = 0]

Not bit-addressable

This register controls the MUX that determines the source of the system clock. See the Clock section for additional information.

Figure 101. Clock Select (CLK_SEL) Register
7 6 5 4 3 2 1 0
— CLK_SEL1 CLK_SEL0
R/W-0 R/W-0 R/W-0

Table 86. CLK_SEL Register Field Descriptions

Bit Field Type Reset Description
7-2 R/W 0
1 CLK_SEL1 R/W 0 See Table 87.
0 CLK_SEL0 R/W 0 See Table 87.

Table 87. CLK_SELx Bit Configurations

CLK_SEL1 CLK_SEL0 CLOCK MODE
0 0 Internal clock. Ignore synchronization pulse received on the LIN bus
0 1 Internal clock. Process synchronization pulse received on the LIN bus
1 0 External crystal clock
1 1 Internal clock. Ignore synchronization pulse received on the LIN bus.

7.6.2.23 Watchdog Enable Register (offset = 0xBE) [reset = 0]

Not bit-addressable

The oscillator watchdog resets the 8051W core if the main oscillator or external crystal oscillator falls outside the valid range. The software watchdog must be serviced by software every 250ms or it will reset the 8051W core. Both of these watchdogs can be enabled or disabled with this register. See the Main Oscillator Watchdog section for additional information on both of these watchdogs.

Figure 102. Watchdog Enable (WD_EN) Register
7 6 5 4 3 2 1 0
— SW_WD_EN OSC_WD_EN
R/W-0 R/W-0 R/W-0

Table 88. WD_EN Register Field Descriptions

Bit Field Type Reset Description
7-2 R/W 0
1 SW_WD_EN R/W 0 0: Disable software watchdog.
1: Enable software watchdog.
0 OSC_WD_EN R/W 0 0: Disable oscillator watchdog.
1: Enable oscillator watchdog.

7.6.2.24 LIN/SCI Select Register (offset = 0xBF) [reset = 0]

Not bit-addressable

The LIN_SCI bit selects between using the embedded LIN2.1 slave protocol or SCI buffered mode. SCI buffered mode can transmit or receive 8 bytes of data, beyond that the communication protocol is determined by what is programmed in the 8051W software. See the LIN 2.1 Slave and Buffered SCI section for additional information.

Figure 103. LIN/SCI Select (LIN_SCI) Register
7 6 5 4 3 2 1 0
— LIN_SCI
R/W-0 R/W-0

Table 89. LIN_SCI Register Field Descriptions

Bit Field Type Reset Description
7-1 R/W 0
0 LIN_SCI R/W 0 0: LIN bus operates with LIN protocol.
1: LIN bus operates in SCI mode.

7.6.2.25 EEPROM Control Register (offset = 0xC0) [reset = 0]

Bit-addressable

The RELOAD bit in this register copies the contents of the EEPROM into the EEPROM cahce. The WRITE bit programs the EEPROM with the values stored in the EEPROM cache. Programming starts when the WRITE bit is set to 1. The WRITe bit reamins at 1 until the programming is completed, at which point it drops back to 0. See the EEPROM Memory Organization section for additional information.

Figure 104. EEPROM Control (EE_CTRL) Register
7 6 5 4 3 2 1 0
— — RELOAD WRITE/EE_STATUS
R/W-0 R-0 W-0 R/W-0

Table 90. EE_CTRL Register Field Descriptions

Bit Field Type Reset Description
7-3 R/W 0
2 R 0
1 RELOAD W 0 0: No action
1: Reload EEPROM contents to EEPROM buffer.
0 WRITE/EE_STATUS R/W 0 Write:
0: No action
1: Program data in EEPROM buffer into EEPROM.
Read:
0: EEPROM programming is idle.
1: EEPROM is being programmed.

7.6.2.26 Status 1 (STATUS1) Register (offset = 0xC1) [reset = 0]

Not bit-addressable

This register stores power-block diagnostic information as well as information about self-tests. For more information see the Diagnostics section and the Internal ASIC TRIM Validity for the trim test and the FIFO RAM test.

Figure 105. Status 1 (STATUS1) Register
7 6 5 4 3 2 1 0
– TRIM_FAIL MBIST_DONE MBIST_FAIL VPWR_OV AVDD_UV AVDD_OC RBIAS_OC
R/W-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 91. STATUS1 Register Field Descriptions

Bit Field Type Reset Description
7 R/W 0
6 TRIM_FAIL R 0 0: Internal ASIC trim values not corrupted
1: Internal ASIC trim values corrupted
5 MBIST_DONE R 0 0: FIFO RAM built-in self-test complete
1: FIFO RAM built-in self-test did not complete.
4 MBIST_FAIL R 0 0: FIFO RAM built-in self-test passed.
1: FIFO RAM built-in self-test did not pass or did not start.
3 VPWR_OV R 0 0: No overvoltage on VPWR pin
1: Overvoltage on VPWR pin
2 AVDD_UV R 0 0: No undervoltage on AVDD pin
1: AVDD pin voltage < 4.2 V nominal
1 AVDD_OC R 0 0: No overcurrent on AVDD pin
1: AVDD pin current > 55 mA nominal
0 RBIAS_OC R 0 0: No overcurrent on RBIAS pin
1: RBIAS pin current > 63 µA nominal

7.6.2.27 Status 2 Register (offset = 0xC2) [reset = 0]

Not bit-addressable

The VREG_RDY bit is set to 1 when the VREG pin is close to the programmed voltage. The VREG pin should be ready before starting a burst. After the burst is completed, the SAT_DONE bit indicates when the voltage envelope at the LIM pin has decreased to below the programmed saturation threshold. The time that this takes is stored in the SAT_TIME register.

The WD_TO_SW and WD_TO_OSC bits indicate the status of the software and oscillator watchdogs. Note that both watchdogs must be enabled in the WD_EN register to use.

The LSA_FLT and LSB_FLT bits are diagnostic flags for the low-side FET drivers which protect the FETs from sinking excessive currents. This diagnostic must be enabled in the LS_FAULT_LOGIC_EN bit in CONTROL_1 register before use.

Figure 106. Status 2 (STATUS2) Register
7 6 5 4 3 2 1 0
— WD_TO_OSC LSB_FAULT LSA_FAULT WD_TO_SW SAT_DONE VREG_READY
R/W-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 92. STATUS2 Register Field Descriptions

Bit Field Type Reset Description
7-0 R/W 0
5 WD_TO_OSC R 0 0: Internal ocillator is normal.
1: Internal oscillator is abrnormal.
4 LSB_FAULT R 0 0: No Fault on LSB
1: Fault on LSB
3 LSA_FAULT R 0 0: No fault on LSA
1: Fault on LSA
2 WD_TO_SW R 0 0: Software watchdog has not timed out.
1: Software watchdog has timed out and the micro has been reset.
1 SAT_DONE R 0 0: Echo signal is not below saturation threshold.
1: Echo signal is below saturation threshold.
0 VREG_READY R 0 0: VREG is not in regulation.
1: VREG is less than 200 mV (nominal) below set point selected by VREG_SEL bits.

7.6.2.28 Power Mode Register (offset = 0xC3) [reset = 0]

Not bit-addressable

The ACTIVE_EN bit enables the support circtuitry related to burst generation and echo processing. This bit must be set before enabling burst generation or echo processing (both enabled in the EN_CTRL register).

The VREG_EN bit enables a 100-mA current source to charge an external capacitor. This can then be used to drive the primary of a trasformer. The VREG voltage can be controlled through the VREG_SEL register. See the VREG section for additional information.

Figure 107. Power Mode (PWR_MODE) Register
7 6 5 4 3 2 1 0
— VREG_EN ACTIVE_EN
R/W-0 R/W-1 R/W-0

Table 93. PWR_MODE Register Field Descriptions

Bit Field Type Reset Description
7-2 R/W 0
1 VREG_EN R/W 0 0: VREG is disabled.
1: VREG is enabled.
0 ACTIVE_EN R/W 0 0: EEPROM, VPWR_MON, LNA, LS diagnostics, OUTA, OUTB, ADC are disabled.
1: All the foregoing are enabled.

7.6.2.29 Datapath and SCI Control Register (offset = 0xC4) [reset = 0]

Not bit-addressable

This register controls what is loaded into the FIFO RAM. By default, the FIFO is loaded with the digital datapath output, but the FIFO_ADC gives the option of bypassing the datapath altogether and loading the FIFO directly from the ADC. The FIFO_PEAKDET bit determines whether or not the low-pass filter is used in the digital datapath.

The SCI_TX_EN bit is used while transmitting through SCI. See the SCI Buffered Mode section for additional information on SCI communication procedures.

Figure 108. Datapath and SCI Control (DP_SCI_CTRL) Register
7 6 5 4 3 2 1 0
— FIFO_ADC SCI_TX_EN FIFO_PEAKDET
R/W-0 R/W-0 R/W-1 R/W-1

Table 94. DP_SCI_CTRL Register Field Descriptions

Bit Field Type Reset Description
7-3 R/W 0
2 FIFO_ADC R/W 0 0: FIFO is loaded with digital datapath output
1: FIFO is loaded with ADC output.
1 SCI_TX_EN R/W 0 0: No action
1: SCI transmit enable
0 FIFO_PEAKDET R/W 0 0: In the digital datapath, the lowpass filter is used.
1: In the digital datapath, the lowpass filter is bypassed and the peak-detector output is used (No low-pass filtering).

7.6.2.30 FIFO Control Register (offset = 0xC5) [reset = ]

Not bit-addressable

The digital datapath has a resolution of 12 bits; however, to conserve space in the FIFO RAM, there are several options about how to store the data from the datapath into the FIFO. All 12 bits can be stored, which effectively halves the number of data points that can be stored in the FIFO. The other three options include the lower eight bits, the upper eight bits, and the middle eight bits. The lower and middle eight bit options also include a saturation check. If there is an overflow, then 0xFF is stored instead of what the lower or middle eight bits actually was.

If FIFO rollover mode is enabled, then the FIFO write pointer will roll over to 0 after all 768 bytes in the FIFO have been written to. After the write pointer rolls over, the FIFO RAM will continue to fill with samples from the digital datapath.

Figure 109. FIFO Control (FIFO_CTRL) Register
7 6 5 4 3 2 1 0
— ROLLOVER FMODE1 FMODE0
R/W-0 R/W-0 R/W-1 R/W-1

Table 95. FIFO_CTRL Register Field Descriptions

Bit Field Type Reset Description
7 R/W 0
2 ROLLOVER R/W 0 0: FIFO rolls at the end.
1: No rollover of the FIFO
1 FMODE1 R/W 0 See Table 96.
0 FMODE0 R/W 0 See Table 96.

Table 96. FMODEx Bit Configuration

FMODE1 FMODE0 DATAPATH BITS STORED INTO THE FIFO
0 0 datapath bits [11:0]
0 1 datapath bits [11:4]
1 0 datapath bits [7:0] with saturation check on datapath bits [11:8]
1 1 datapath bits [10:3] with saturation check on datapath bit [11]

7.6.2.31 Enable Control Register (offset = 0xC8) [reset = 0]

Bit Addressable

The EN_CTRL register is used to initiate a distance measurement. BURST_X_EN enables a burst on the low-side drivers, ECHO_EN starts to fill the FIFO with data from the digital datapath, SAT_EN triggers a saturation measurement for diagnostic purposes, and CAP_FR_TMR captures the free running timer to the free running timer shadow register. These can all be triggered at the same time or individually depending on the application.

Figure 110. Enable Control (EN_CTRL) Register
7 6 5 4 3 2 1 0
CAP_FR_TMR — ECHO_EN SAT_EN BURST_B_EN BURST_A_EN
W-0 R/W-0 R/W-0 R/W-0 W-0 W-0

Table 97. EN_CTRL Register Field Descriptions

Bit Field Type Reset Description
7 CAP_FR_TMR W 0 0: No action
1: Capture free-running timer value to ESFR FRT.
6-4 R/W 0
3 ECHO_EN R/W 0 0: Disable echo processing – the FIFO is not filled.
1: Enable echo processing – the FIFO starts filling after the blanking timer expires.
2 SAT_EN R/W 0 0: Disable saturation monitor function.
1: Enable saturation monitor function.
1 BURST_B_EN W 0 0: No Action
1: Enable burst on OUTB in single-ended
0 BURST_A_EN W 0 0: No action
1: Enable burst on OUTA in single-ended and OUTA/OUTB in push-pull.

7.6.2.32 LIN/SCI Rx Data (RX_DATAx) Register (offset = 0xC9 to 0xD1) [reset = 0]

Not bit-addressable

Received data from LIN/SCI is stored in the RX_DATAx register. See the LIN 2.1 Slave and Buffered SCI section for more information about LIN/SCI communication.

Figure 111. LIN/SCI Rx Data (RX_DATAx) Register
7 6 5 4 3 2 1 0
RX_DATAx[7] RX_DATAx[6] RX_DATAx[5] RX_DATAx[4] RX_DATAx[3] RX_DATAx[2] RX_DATAx[1] RX_DATAx[0]
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 98. RX_DATAx Register Field Descriptions

Bit Field Type Reset Description
7-0 RX_DATAx[7:0] R 0

7.6.2.33 LIN PID Register (offset = 0xD2) [reset = 0]

Not bit-addressable

The LIN_PID register is used to store the received PID frame from the most recent LIN message. This can be interpreted by the PGA450-Q1 application firmware to determine how to respond to the message. See the LIN 2.1 Slave and Buffered SCI section for more information about LIN/SCI communication.

Figure 112. LIN PID (LIN_PID) Register
7 6 5 4 3 2 1 0
PID7 PID6 PID5 PID4 PID3 PID2 PID1 PID0
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 99. LIN_PID Register Field Descriptions

Bit Field Type Reset Description
7 PID7 R 0
6 PID6 R 0
5 PID5 R 0
4 PID4 R 0
3 PID3 R 0
2 PID2 R 0
1 PID1 R 0
0 PID0 R 0

7.6.2.34 LIN/SCI Tx Data Registers (offset = 0xD3 to 0xDA) [reset = 0]

Not bit-addressable

Data to be transmitted over LIN/SCI from the PGA450-Q1 must be programmed to the TX_DATAx register before triggering a transmit message via the RX_TX bit in the LIN_CTRL register. The number of bytes transmitted is set by the DATA_CNT register. See the LIN 2.1 Slave and Buffered SCI section for more information about LIN/SCI communication.

Figure 113. LIN/SCI Tx Data (TX_DATAx) Registers
7 6 5 4 3 2 1 0
TX_DATAx[7] TX_DATAx[6] TX_DATAx[5] TX_DATAx[4] TX_DATAx[3] TX_DATAx[2] TX_DATAx[1] TX_DATAx[0]
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 100. TX_DATAx Register Field Descriptions

Bit Field Type Reset Description
7-0 TX_DATAx[7:0] R/W 0

7.6.2.35 LIN/SCI Data Count Register (offset = 0xDB) [reset = 0]

Not bit-addressable

The DATA_CNT register determines how many bytes of data will be sent from the TX_DATAx register when a LIN/SCI transmit is initiated. When in SCI mode, the minimum DATA_CNT should be. In both LIN and SCI mode, the maximum value of DATA_CNT should be 8. See the LIN 2.1 Slave and Buffered SCI section for more information about LIN/SCI communication.

Figure 114. LIN/SCI Data Count (DATA_CNT) Register
7 6 5 4 3 2 1 0
— CNT3 CNT2 CNT1 CNT0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 101. DATA_CNT Register Field Descriptions

Bit Field Type Reset Description
7-4 R/W 0
3 CNT3 R/W 0
2 CNT2 R/W 0
1 CNT1 R/W 0
0 CNT0 R/W 0

7.6.2.36 LIN Configuration Register (offset = 0xDC) [reset = 0x40]

Not bit-addressable

The LIN_CFG register sets the checksum type used and LIN diagnostics used. See the LIN 2.1 Slave and Buffered SCI section for more information about LIN/SCI communication.

Figure 115. LIN Configuration (LIN_CFG) Register
7 6 5 4 3 2 1 0
BIT_TOL CS_METHOD CLR_ERR INTERBYTE_SPC HOLD — IGNORE_DIAG —
R/W-0 R/W-1 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 102. LIN_CFG Register Field Descriptions

Bit Field Type Reset Description
7 BIT_TOL R/W 0 0: Normal bit-time tolerance for the STOP bit transmitted after PID and data. The nominal is 15% of the expected bit rate.
1: Doubles the bit-time tolerance to 30% for the STOP bit transmitted after PID and data.
6 CS_METHOD R/W 1 0: Classic checksum
1: Enhanced checksum
5 CLR_ERR R/W 0 0: Do not clear LIN error log register (LIN_STATUS). The clear occurs only between frames.
1: Clear error log register (LIN_STATUS).
4 INTERBYTE_SPC R/W 0 0: 1 bit of inter-byte space during transmission of data bytes by PGA450-Q1
1: 2 bits of inter-byte space during transmission of data bytes by PGA450-Q1
3 HOLD R/W 0 0: LIN frame is not ignored.
1: LIN Frame is ignored; that is, the LIN slave protocol does not process the break field.
2 R/W 0 This bit should always be written as 0; the user software should not write a 1 to this bit.
1 IGNORE_DIAG R/W 0 0: Wait for data bytes after PID is received.
1: Wait for break field after PID is received.
0 R/W 0 This bit should always be written as 0; the user software should not write a 1 to this bit.

7.6.2.37 LIN Control Register (offset = 0xDD) [reset = 0]

Not bit-addressable

The RX_TX bit initiates a receive or transmit for LIN or SC depending on the mode currently chosen by the LIN_SCI register. See the LIN 2.1 Slave and Buffered SCI section for more information about LIN/SCI communication.

Figure 116. LIN Control (LIN_CTRL) Register
7 6 5 4 3 2 1 0
— RX_TX
R/W-0 R/W-0

Table 103. LIN_CTRL Register Field Descriptions

Bit Field Type Reset Description
7-1 R/W 0
0 RX_TX R/W 0 0: Receive data on LIN bus
1: Transmit data on LIN bus

7.6.2.38 LIN STATUS Register (offset = 0xDE) [reset = 0]

Not bit-addressable

The LIN_STATUS register holds the LIN diagnostics, parity, and checksum information. See the LIN 2.1 Slave and Buffered SCI section for more information about LIN/SCI communication.

Figure 117. LIN STATUS (LIN_STATUS) Register
7 6 5 4 3 2 1 0
— BREAK_DEL SYNC_LONG SYNC_SHORT STOP_BIT_SHORT STOP_BIT_VAL PARITY CHECKSUM
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 104. LIN_STATUS Register Field Descriptions

Bit Field Type Reset Description
7 R 0
6 BREAK_DEL R 0 0: Break delimiter normal
1: Break delimiter is shorter than expected.
5 SYNC_LONG R 0 0: Sync is not long.
1: Sync is longer than expected (based on fixed time of 50 µs/bit)
4 SYNC_SHORT R 0 0: Sync is not short.
1: Sync is shorter than expected (based on fixed time of 50 µs/bit).
3 STOP_BIT_SHORT R 0 0: Stop bit is normal.
1: Stop bit of PID and data is short (based on configuration of bit rate tolerance).
2 STOP_BIT_VAL R 0 0: Stop bit valid
1: Stop bit was not set after 8th LIN bit was received or transmitted
1 PARITY R 0 0: PID parity no error
1: PID parity error
0 CHECKSUM R 0 0: Checksum normal
1: Checksum error

7.6.2.39 FIFO Pointer (FIFO_POINTER) Registers

Not bit-addressable

The FIFO pointer registers indicate the current location in the FIFO RAM read to be written to once a sample is available from the digital datapath. By checking the current status of the FIFO pointer in the PGA450-Q1 application firmware, the user can ensure that the algorithm processing the echo data in the FIFO does not surpass the valid available data.

7.6.2.39.1 FIFO Pointer MSB Register (offset = 0xDF) [reset = 0]

Figure 118. FIFO Pointer MSB (FIFO_POINTER_MSB) Register
7 6 5 4 3 2 1 0
— FIFO_PTR[9] FIFO_PTR[8]
R-0 R-0 R-0

Table 105. FIFO_POINTER_MSB Register Field Descriptions

Bit Field Type Reset Description
7-2 R 0
1-0 FIFO_PTR[9:8] R 0

7.6.2.39.2 FIFO Pointer LSB Register (offset = 0xE1) [reset = 0]

Figure 119. FIFO Pointer LSB (FIFO_POINTER_LSB) Register
7 6 5 4 3 2 1 0
FIFO_PTR[7] FIFO_PTR[6] FIFO_PTR[5] FIFO_PTR[4] FIFO_PTR[3] FIFO_PTR[2] FIFO_PTR[1] FIFO_PTR[0]
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 106. FIFO_POINTER_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 FIFO_PTR[7:0] R 0

7.6.2.40 VREG Select Register (offset = 0xE2) [reset = 0]

Bit-addressable

The VREG_SEL register dermines what voltage VREG will be regulated to when enabled. Note that VPWR must be at least 2 V greater than the selected VREG voltage to ensure proper VREG regulation.

Figure 120. VREG Select (VREG_SEL) Register
7 6 5 4 3 2 1 0
— — VREG_SEL3 VREG_SEL2 VREG_SEL1 VREG_SEL0
W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 107. VREG_SEL Register Field Descriptions

Bit Field Type Reset Description
7 W 0
6-4 R/W 0
3 VREG_SEL3 R/W 0 See Table 108.
2 VREG_SEL2 R/W 0 See Table 108.
1 VREG_SEL1 R/W 0 See Table 108.
0 VREG_SEL0 R/W 0 See Table 108.

Table 108. VREG_SELx Bit Configuration

VREG_SEL3 VREG_SEL2 VREG_SEL1 VREG_SEL0 NOMINAL VREG VOLTAGE (V)
0 0 0 0 4.7
0 0 0 1 4.8
0 0 1 0 4.9
0 0 1 1 5.0
0 1 0 0 5.1
0 1 0 1 5.2
0 1 1 0 5.3
0 1 1 1 5.4
1 0 0 0 7.7
1 0 0 1 7.8
1 0 1 0 7.9
1 0 1 1 8.0
1 1 0 0 8.1
1 1 0 1 8.2
1 1 1 0 8.3
1 1 1 1 8.4

7.6.2.41 Sync Count (SYNC_COUNT) Registers

Not bit-addressable

The SYNC_COUNT register can be used to determine the success of a LIN sync operation. This register stores the measured width of the LIN sync field. See the Clock Synchronizer Using the SYNC Field in the LIN Bus section for more details.

7.6.2.41.1 Sync Count MSB Register (offset = 0xE3) [reset = 0]

Figure 121. Sync Count MSB (SYNC_COUNT_MSB) Register
7 6 5 4 3 2 1 0
SC[15] SC[14] SC[13] SC[12] SC[11] SC[10] SC[9] SC[8]
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 109. SYNC_COUNT_MSB Register Field Descriptions

Bit Field Type Reset Description
7-0 SC[15:8] R 0

7.6.2.41.2 Sync Count LSB Register (offset = 0xE4) [reset = 0]

Figure 122. Sync Count LSB (SYNC_COUNT_LSB) Register
7 6 5 4 3 2 1 0
SC[7] SC[6] SC[5] SC[4] SC[3] SC[2] SC[1] SC[0]
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0

Table 110. SYNC_COUNT_LSB Register Field Descriptions

Bit Field Type Reset Description
7-0 SC[7:0] R 0

7.6.2.42 TEMP/DAC Control Register (offset = 0xE5) [reset = 0]

Bit-addressable

Figure 123. TEMP/DAC Control (TEMP_DAC_CTRL) Register
7 6 5 4 3 2 1 0
— — TS_DAC_MODE TS_DAC_EN
W-0 R/W-0 W-0 W-0

Table 111. TEMP_DAC_CTRL Register Field Descriptions

Bit Field Type Reset Description
7 W 0
6-2 R/W 0
1 TS_DAC_MODE W 0 0: Temperature sensor
1: Digital datapath
0 TS_DAC_EN W 0 0: Temperature sensor DAC powered off
1: Temperature sensor DAC powered on

7.6.2.43 Oscillator Sync Control Register (offset = 0xE6) [reset = 0]

Bit-addressable

The OSx bits determine how much of an oscillator frequency shift is implemented. This can be determined from the LIN synchronization algorithm or directly from the 8051W application code. See Table 3 for details on what frequency shifts are implemented from the OSx bits.

Figure 124. Oscillator Sync Control (OSC_SYNC_CTRL) Register
7 6 5 4 3 2 1 0
— OVR OS5 OS4 OS3 OS2 OS1 OS0
W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 W-0 W-0

Table 112. OSC_SYNC_CTRL Register Field Descriptions

Bit Field Type Reset Description
7 W 0
6 OVR R/W 0 0: OS[5:0] are read-only for 8051W, clock synchronization algorithm updates OS[5:0] bits.
1: 8051W updates OS[5:0] bits, clock synchronization algorithm does not update OS[5:0] bits.
5 OS5 R/W 0
4 OS4 R/W 0
3 OS3 R/W 0
2 OS2 R/W 0
1 OS1 W 0
0 OS0 W 0

7.6.3 TEST Registers

7.6.3.1 ANALOG Test MUX Register (offset = 0xE9) [reset = 0]

Not bit-addressable

The AMUX register determines what the output of the DACO pin is. Both options for the DAC output are intended for development purposes as they provide ways to view the echo signal on an oscilloscope before and after the digital datapath.

Figure 125. ANALOG Test MUX (AMUX) Register
7 6 5 4 3 2 1 0
— AMUX3 AMUX2 AMUX1 AMUX0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 113. AMUX Register Field Descriptions

Bit Field Type Reset Description
7-4 R/W 0
3 AMUX3 R/W 0 See Table 114.
2 AMUX2 R/W 0 See Table 114.
1 AMUX1 R/W 0 See Table 114.
0 AMUX0 R/W 0 See Table 114.

Table 114. AMUX3:0 Bit Configuration

AMUX3:AMUX0 (Hexadecimal) Output on TESTO_A Description
01 DAC OUTPUT Digital datapath output voltage
04 LNA OUTPUT Low-noise amplifier output

7.6.3.2 DIGITAL Test MUX Register (offset = 0xEA) [reset = 0]

Not bit-addressable

Figure 126. DIGITAL Test MUX (DMUX) Register
7 6 5 4 3 2 1 0
— DMUX4 DMUX3 DMUX2 DMUX1 DMUX0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

Table 115. DMUX Register Field Descriptions

Bit Field Type Reset Description
7-5 R/W 0
4 DMUX4 R/W 0 See Table 116.
3 DMUX3 R/W 0 See Table 116.
2 DMUX2 R/W 0 See Table 116.
1 DMUX1 R/W 0 See Table 116.
0 DMUX0 R/W 0 See Table 116.

Table 116. DMUX4:0 Bit Configuration

DMUX4:DMUX0 (Hexadecimal) Output on TESTO_D Description Output on GPIO1 Description Output on GPIO2 Description
01 SAT_EN Saturation enable SAT_DONE Saturation Done SAT_MON Saturation Comparator Output
04 LIN_RXD LIN receive LIN_TXD LIN Transmit
08 FIFO_UPDATE Pulse is generated when FIFO pointer is updated.
0A CLK System clock INT_CLK Internal Clock EXT_CLK External Clock