Over the last year or so we’ve noticed a definite uptick in the number of folks using OpenOCD on the Raspberry Pi. It’s a cheap and convenient solution for poking around with various microcontrollers and embedded devices, but not always the most elegant. Looking to improve on the situation somewhat, [Matthew Mets] has been working on a purpose-built JTAG Hat to clean things up a bit.
Onboard level shifters allow you connect to JTAG and SWD interfaces from 1.8 to 5 V, and if you power the target device from the Pi itself, there’s even support for measuring the voltage and current. To connect up to your target, the open hardware board features a “legacy” pin header perfect for jumper wires, as well as a dedicated 10-pin Cortex Debug Connector. Whether you spin up your own or buy one assembled, it certainly looks like a tool worth having around if you often find yourself working with the appropriate chips.
In addition to the design files for the hardware, [Matthew] has also provided some nice documentation on how to get the software side of things up and running. Starting with a blank SD card, it walks you through the initial setup of the Raspberry Pi all the way through the installation and configuration of a patched version of OpenOCD designed to support the JTAG Hat.
If you spend more time working with 8-bit AVR chips, don’t worry. Last year we covered a similar project to turn everyone’s favorite Linux SBC into an all-in-one microcontroller development powerhouse.