3 ms·
The timing on the SWIO interface needs to be within a few hundred nanoseconds if you want decent bandwidth, but I suppose there's nothing stopping you from runn
by aappleby 3y ago
The timing on the SWIO interface needs to be within a few hundred nanoseconds if you want decent bandwidth, but I suppose there's nothing stopping you from running it on a slower and less real-time GPIO pin. You'd just need to swap out the implementation of the PicoSWIO class, the rest would be identical.
- zamnos 3y agoThe RaspberryPi has a SMI mode that should be able to handle 62 MhZ on a single pin usefully, did you investigate using that at all?
- aappleby 3y agoI'm not familiar with that interface, but I suspect it would have similar issues with timing tolerances as just bit-banging gpios.
- zamnos 3y agoIt's a programmable, parallel data bus, like you'd get on an old school micro to access external rom and ram. It'll DMA to/from the Pi's RAM, and has programmable timings for read and write signaling, so it's not at all like bit-banging GPIOs. The only question is if it's usable for your debugger project, as it's not meant for that.
- vardump 3y agoPico is more than capable of handling timing within a few hundred nanoseconds with it's PIO (programmable IO) functionality. You don't usually ever need to bitbang with RP2040.