I tried to use picoprobe to debug an nrf52 chip, it failed to even detect it.. All that’s officially supported is using it to debug a raspberry pi, and maybe if I added 100Ohm resistors to the lines I would have had better luck, but.. alas
> I tried to use picoprobe to debug an nrf52 chip, it failed to even detect it
I've literally got a Pi Debug Probe and a nRF52840 dev board on my desk, so I gave it a shot - and it works just fine. Make sure the core is awake when you try to connect for debug, or connect under reset; SWD goes to sleep with the rest of the chip.
> All that’s officially supported is using it to debug a raspberry pi
The Pi Debug Probe is a generic DAPlink probe, and will work for pretty much any Cortex-M part. I routinely use mine for debugging STM32 parts.
'Connect under reset' is an STM32 thing, nrf52840 can't really do that and the probe doesn't use hardware reset pin. Once the MCU is out of pin reset, Ctrl-AP can hold the mcu in soft reset, but that's the standard behavior.
The difference between Pico and Pi Debug Probe are those 100Ω resistors on CLK/DIO lines, so I guess it working for you means I need to try again with resistors soldered.
There's basically zero chance 100Ω resistors are contributing to your issues on a protocol that is host-clocked and can operate in the single kilobaud range.
Lower speed or try one of the other fifty debug firmware projects.
Okay i'm officially a dumbass - looking at the pinout i can clearly see Arduino pins and normal GPIO pins are mixed up on the board I used (seeed xiao rp2040). Arduino strikes again!
Just checked - of course if works fine on proper pins
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