probe: add CMSIS-DAP PIO-driven implementation CMSIS-DAP implementations explicitly use CPU bitbash to control SWD and SWDIO, but we can do better. Transfers are handed off to PIO in phases, which gets us deterministic clock timing as well as freeing the CPU up for other tasks. Signed-off-by: Jonathan Bell <jonathan@raspberrypi.com>
Picoprobe allows a Pico / RP2040 to be used as USB -> SWD and UART bridge. This means it can be used as a debugger and serial console for another Pico.
Picoprobe documentation can be found in the Pico Getting Started Guide. See “Appendix A: Using Picoprobe”.