1.2.7.1 Debugging UART, I²C, SPI and CAN Bootloaders for Cortex-M Based MCUs

The UART, I²C, SPI and CAN bootloaders for Cortex-M based MCU's are designed to run from SRAM to support:

• Simultaneous Flash memory write and reception of the next block of data

• Self update

  

• For debugging these bootloaders make use of software breakpoints instead of Hardware breakpoints

Steps to enable software breakpoints and start debugging

• Enable software breakpoint from the project configuration dashboard by clicking the button as shown below

• Software breakpoints inside main() when running from SRAM do not work when set before starting the debugger

  • For them to work first set a Breakpoint in startup_xc32.c file as it is running from Flash

  

• Start the debugger from MPLAB IDE and the software break point in startup file will be hit

  

• Once the breakpoint is hit in startup file, then set breakpoints anywhere the user wants, such as in main() function as shown below

  

• Resume the debugger and the user should be able to debug as usual