Bumpy's blackmagic probe firmware supports many platforms, but our board was primarily designed for use with our Nordic Semiconductor nRF BLE boards. When we built our Bluey nRF52 BLE dev board, we were looking for an inexpensive option for our users to upload code to bluey and debug it using ARM GDB. We then came across the blackmagic probe (BMP) project - an Open Source debugging tool for embedded microprocessors. It greatly simplifies the debugging and code uploading process using just ARM GDB - no need to run a GDB server or use an additional complex tool like openocd. Although their hardware is excellent, BMP was a bit beyond our budget. So we decided to make use of their liberal Open Source license and build something that fits our budget, albeit with less capabilities.
Project files below: