SLLU349 August   2022

 

  1.   Abstract
  2.   Trademarks
  3. 1Read This First
    1. 1.1 Information About Cautions and Warnings
    2. 1.2 FCC Warning
  4. 2What is in the Box
    1. 2.1 List of Hardware Items for Operation
    2. 2.2 List of Software Items for Operation
  5. 3Summary of Hardware Design
    1. 3.1 Ribbon-Cable Connector J2 and Pinout
    2. 3.2 Configuration of Pullup Resistors for Pins 8, 9, and 10
    3. 3.3 LED Indication of USB Attached
    4. 3.4 Step-by-Step Instructions for Operation and Troubleshooting
  6. 4PMBUS and SMBUS Communications
    1. 4.1 Basic SMBUS Transaction Types Supported
    2. 4.2 Special Signals Used for PMBUS and SMBUS Communications
    3. 4.3 Packet Error Checking (PEC) Implementation
    4. 4.4 Communication Clock Speed and Clock Stretching

3.2 Configuration of Pullup Resistors for Pins 8, 9, and 10

The pullups for pins 8, 9, and 10 are configurable through communications with the embedded firmware in the USB interface. The default setting is for all these three pins to have pullups of 2.2 kΩ. Table 3-2 lists the possible options for each pin.

Table 3-2 Configurable Options of Pullup Resistors for Pins 8, 9, and 10
Pullup Resistor Option (Byte Value)Option 1
(0x00)		Option 2
(0x01) (Default)		Option 3
(0x02)		Option 4
(0x03)
Pin 8 of J2: ALERT lineNo pullup (open)2.2 kΩN/AN/A
Pin 9 of J2: CLOCK lineNo pullup (open)2.2 kΩ1 kΩ499 Ω
Pin 10 of J2: DATA lineNo pullup (open)2.2 kΩ1 kΩ499 Ω