05-25-2020, 08:46 AM
(05-06-2020, 07:31 AM)danielt Wrote:(02-28-2020, 10:15 PM)cjmakes Wrote:(02-24-2020, 06:36 AM)wibble Wrote: Are you sure it's the same error? You say you're using the bcm2835spi driver, but the debug output above is for the bitbanging bcm2835gpio driver.
Yes, different driver, same error.
Had you *previously* been using the bcm2835spi driver?
AFAICT bcm2835spi contains a sneaky trick where both the RPi and the nRF52 will be outputting data on the SWDIO pin at the same time (e.g. the RPi pushes 0v whilst the nRF52 pushes 3v3 for some cycles). Without some kind of current limiting resistor inline on the SWDIO line then this sounds a bit risky to me
I added a 330Ω inline resistor which should result in safe 10mA max current in this case but the error still appeared. Also if it was a real short I'd expect the device be a little more broken or at least behave like being disconnected (if you assume that the port is damaged) but it behaves differently.
