SWRU437B September   2015  – June 2020 WL1801MOD , WL1805MOD , WL1807MOD , WL1831MOD , WL1835MOD , WL1837MOD

 

  1.   WiLink Module Hardware Integration Guide
    1.     Trademarks
    2. 1  Module Variant Table
      1. 1.1 WiLink WLAN Antenna Configuration
        1. 1.1.1 Single-Input Single-Output (SISO)
        2. 1.1.2 Multiple-Input Multiple-Output (MIMO)/Maximum Ratio Combining (MRC)
    3. 2  Critical Connections
    4. 3  Power Supply
      1. 3.1 Power Up/Shutdown Sequence
        1. 3.1.1 Power Up
        2. 3.1.2 Shutdown
      2. 3.2 Power Sequencing
    5. 4  Clocks
      1. 4.1 Slow Clock
      2. 4.2 Fast Clock
    6. 5  Current Consumption
      1. 5.1 Performance Parameters - Typical
    7. 6  Antenna
    8. 7  Ground Connections
    9. 8  Layout
    10. 9  Hardware Troubleshoot
      1. 9.1 System Requirements
      2. 9.2 Power Rails
      3. 9.3 Critcal Supplies
      4. 9.4 Sense on Reset
      5. 9.5 WLAN
        1. 9.5.1 WLAN Host Interface (SDIO)
        2. 9.5.2 WLAN IRQ Operation (SDIO Out-of-Band Interrupt)
      6. 9.6 Bluetooth and Bluetooth Low Energy
        1. 9.6.1 Bluetooth UART HCI Interface
        2. 9.6.2 Bluetooth PCM
      7. 9.7 Reserved Pins
      8. 9.8 Debug
    11. 10 WiFi_Zigbee Coex
    12. 11 References
  2.   Revision History

9.5.2 WLAN IRQ Operation (SDIO Out-of-Band Interrupt)

The WLAN IRQ is an out-of-band interrupt request line that is not defined by the SDIO standard specification. Therefore, a good understanding on how it works is required in order to work with the WL8xx solution.

The WLAN_IRQ line operates as follows:

  • The default state of the WLAN_IRQ prior to device enable is internal 100K pulldown (in case of a debug mode there is external 10K pull up)
  • After the enable line is applied high, the WL_IRQ is changed to drive logic '0'.
  • During firmware initialization, the WLAN_IRQ is configured by the SDIO module.
    • The WLAN firmware creates an interrupt-to-host request, indicated by a 0-to-1 transition on the WLAN_IRQ line (the host must be configured as active high or rising-edge detect).
    • After the host is available, depending on the interrupt priority and other host tasks, it masks the firmware interrupt. The WLAN_IRQ line returns to 0 (a 1-to-0 transition on the WLAN_IRQ line).
    • The host reads the internal register status to determine the interrupt sources. The register is cleared after the read.
    • The host processes all the interrupts read from this register in sequence.
    • The host unmasks the firmware interrupts.
  • The host is ready to receive another interrupt from the WLAN device.
wlan_irq_operation.gifFigure 7. WLAN_IRQ Signal on System Wake Up

For more details on the Wake on Wlan feature, see [3].