Debugging your Model T Using GDB

At the top of the directory run the following in a terminal:

• openocd -f interface/olimex-arm-usb-tiny-h.cfg -f target/stm32f2x.cfg -f stm32f2x-setup.cfg -c init -c "reset init" -c halt -c "stm32f2x.cpu configure -rtos auto”

In a separate terminal run:

• arm-none-eabi-gdb.exe build/app_mt/app_mt.elf --eval-command "target remote:3333" --eval-command "monitor poll" --eval-command "monitor reset halt"

You can now debug in the gdb window. Some useful commands:

• monitor reset halt - (resets the device and stops it so you can setup a new session)
• info threads - (shows a list of the current chibios threads, their states and current program counters)
• thread <#> - (where <#> is the thread id from the 'info threads' list) switches to that thread context
• thread apply <#> bt - (shows a backtrace for a given thread)
• Printing dbg_panic_msg should help narrow down which error happened
• If a hard fault exception is generated, you can inspect the registers that are dumped to stack variables in the handler
• PC (program counter) and LR (link register) will be of most interest Information on those registers is in the .map file