nrfjprog ---pinreset not working on nRF52

RE: nrfjprog ---pinreset not working on nRF52

AmiguelS — Tue, 21 Mar 2017 14:48:02 GMT

@endnode Would pulling the reset pin (P0.21) low be enough to properly reset the device and enter normal mode?

RE: nrfjprog ---pinreset not working on nRF52

AmiguelS — Tue, 21 Mar 2017 13:53:58 GMT

@endnode I also looked through the documentation and found very little additional info. It says -r performs a soft-reset, and -p performs a pin reset, by pin reset I'm assuming they mean hard reset.

On the schematic of the nRF52 DK, nReset is indeed connected to pin P0.21, as seen on page 4.

RE: nrfjprog ---pinreset not working on nRF52

endnode — Tue, 21 Mar 2017 13:39:53 GMT

Yes, I believe P0.21/RESET should be connected to SWD nReset wire, but I cannot find in NRFTOOLS docs what is difference between nrfjprog -p and nrfjrpog -r, I only assume...

RE: nrfjprog ---pinreset not working on nRF52

AmiguelS — Tue, 21 Mar 2017 13:21:37 GMT

@endnode There is nothing connected to P0.21/RESET. Should this be connected to nReset? When the pinreset command is issued, the current consumption increases slightly (for about 3 seconds), the Segger LED blinks green a couple of times and blinks red one time. However, the chip does not reset.

nrfjprog -r -f NRF52 does in fact reset the chip, but apparently it doesn't bright it out of debug mode, since the current consumption goes back to where it was (~2mA).

RE: nrfjprog ---pinreset not working on nRF52

endnode — Tue, 21 Mar 2017 12:31:52 GMT

I guess PINRESET needs separate SWD RST wire attached, do you have it? Otherwise use nrfjprog -r -f NRF52 which sends reset command over SWD protocol, just note that this doesn't work if you have locked nRF52 chip (read back protection which disables whole debugging interface).