ST67W611M1 Not Waking Up After T01 Firmware Flash - SPI_RDY Remains Low

[hrishikeshmanjarekar]

Hi ST team,

I am currently evaluating the ST67W611M1 Wi-Fi module in NCP mode and am facing an issue where the module does not appear to boot correctly after firmware programming.

Hardware Setup

• Module: ST67W611M1
• Supply Voltage: 3.3V
• CHIP_EN: Driven High (3.3V)
• BOOT pin: Connected to GND (Normal Boot Mode)
• SPI_CS: Held High
• Firmware: T01 mission firmware (st67w611m_mission_t01_v2.0.106.bin)
• Programming Method: Standalone firmware download using USB-to-TTL UART
• Host MCU:  STEVAL STWINBX1 Development kit. (STM32U585)

Issue

After powering the module:

1. CHIP_EN goes high correctly.
2. BOOT remains low.
3. Supply is stable at 3.3V.
4. However, SPI_RDY never asserts high.
5. I also do not see any activity on the SPI_RDY pin using an oscilloscope.
6. Because SPI_RDY never goes high, the host cannot proceed with SPI communication.

Verification Already Performed

SPI Signals

I have verified:

• SPI_CLK
• SPI_MOSI
• SPI_MISO
• SPI_CS

SPI Configuration: 

• Baud rate: 5 MBits/s and 2.5 MBits/s
• SPI Mode: 0
• SPI Port: SPI2 on STM32U585
• ReadyMasterManagement - SPI_RDY_MASTER_MANAGEMENT_INTERNALLY

Signal routing and GPIO configuration on the STM32 side appear correct.

Oscilloscope Observation

The attached scope capture shows:

• CH1 (Yellow): CHIP_EN transitions high and remains high.
• CH2 (Blue):  SPI_RDY remains low and never toggles.

Additional Checks

• Performed multiple power cycles after flashing.
• Confirmed BOOT pin is low during power-up.
• Confirmed 3.3V supply is present and stable.
• Measured approximately 1.76V on the 32K_OUT pin and observed a frequency around 1.248 kHz, which seemed unusual.
• SPI_CS kept high while waiting for the device to complete boot.

Questions

1. After successfully flashing the T01 mission firmware (st67w611m_mission_t01_v2.0.106.bin), should SPI_RDY automatically go high after power-up?
2. Is SPI_RDY dependent on any host-side SPI initialization sequence, or should it rise independently once the module boots?
3. Is there any way to confirm that the T01 firmware has booted correctly through UART logs or another status pin?
4. Does the observed behavior on the 32K_OUT pin indicate that the firmware is not booting correctly?
5. Are there any mandatory pin states, reset timing requirements, or power-up sequences beyond:
   • BOOT = Low
   • CHIP_EN = High
   • SPI_CS = High
   • 3.3V Supply
6. Is there a recommended standalone test procedure to verify the module has booted before integrating the full ST67 middleware?

Any guidance on how to determine whether the issue is related to firmware boot, hardware configuration, SPI_RDY behavior, or power sequencing would be greatly appreciated.

Thank you.