Reinstall Raspberri Pi CM4 EEPROM firmware

Cause: This LED pattern indicates a firmware error on the Compute Module 4 (CM4).

Resolution (on Windows): Flash the Raspberry Pi bootloader onto the CM4.

  1. Open the procedure How to re-install the operating system.
  2. Follow steps 1–7 of the section Reinstall Home Assistant OS using rpiboot.
  3. On Windows, open the Command Prompt window (cmd).
  4. Run the following commands:
    cd \
    cd "Program Files (x86)"
    cd "Raspberry Pi"
    rpiboot.exe -d recovery

    Result: The green LED lights up solid, then starts flashing.

  5. Wait for about 1 minute.
    1. Then, from Home Assistant Yellow, unplug the power cable.
    2. Ensure JP1 is set to UART.
  6. On Home Assistant Yellow, connect the power cable.

    Result: The error blink pattern should no longer occur.
    The LED pattern depends on what is already installed on Yellow. Typically, the system should boot now. If Home Assistant OS is installed, the yellow LED should show a heartbeat pattern after ~5 seconds.