Debug monitor
Overview
The Debug Monitor sample shows a basic configuration of debug monitor feature.
The source code shows how to:
- Configure registers to enable degugging in debug monitor mode 
- Specify custom interrupt to be executed when entering a breakpoint 
Requirements
Your board must:
- Support Debug Monitor feature (available on Cortex-M processors with the exception of Cortex-M0) 
- Have an LED connected via a GPIO pin (these are called “User LEDs” on many of Zephyr’s Supported Boards). 
- Have the LED configured using the - led0devicetree alias.
Building and Running
Build and flash Debug Monitor as follows, changing reel_board for your board:
west build -b reel_board samples/subsys/debug/debugmon
west flash
After flashing the board enters a breakpoint and executes debug monitor exception code. The LED starts to blink, indicating that even though the processor spins in debug monitor interrupt, other higher priority interrupts continue to execute.