Debugging Safety Button State in ArduPilot's IOMCU Firmware

ArduCopter
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1

I am working on modifying the ArduPilot codebase to read the state of the safety button. Here’s what I’ve done so far:

  1. Modifying safety_update:
    Inside /ardupilot/libraries/AP_IOMCU/iofirmware, in the void AP_IOMCU_FW::safety_update(void) method, Im using the following line to read the button state:
    bool safety_pressed = palReadLine(HAL_GPIO_PIN_SAFETY_INPUT);

After reading the button state, I pass the value of safety_pressed to a new method I created in AP_HAL_CHIBIOS.

I added a method in AP_HAL_CHIBIOS to store the safety_pressed value received from the previous method. I also created another method in AP_HAL_CHIBIOS to return the safety_pressed value.

From another file in the library folder, I call the method to retrieve safety_pressed and print the value using:
GCS_SEND_TEXT(MAV_SEVERITY_INFO, “Safety Button State: %d”, safety_pressed);

But the problem is:
The value of safety_pressed always remains 0, even when I press the safety button.

Did I miss something???
i also compile the firmware the iomcu
and then i compile and upload the copter to the pixhawk orange cube

Any guidance or insights would be greatly appreciated.

Thank you!