Does nRFgo Studio 1.20.0 "release" the nRF51822 SWDIO pin to be used as a chip reset?

RE: Does nRFgo Studio 1.20.0 "release" the nRF51822 SWDIO pin to be used as a chip reset?

David Fritsch — Mon, 17 Aug 2015 13:32:26 GMT

Thanks Hung! This made a difference for me. After adding NRF_POWER>RESET=1 to my application code (first line in main()), my Nordic chip reset works both after debugging in Keil, and after programming with nRGgo Studio 1.20.0.

RE: Does nRFgo Studio 1.20.0 "release" the nRF51822 SWDIO pin to be used as a chip reset?

Hung Bui — Mon, 17 Aug 2015 10:43:38 GMT

@David Fritsch: It was the fact that nRFGo Studio will leave the chip in debug mode after programming (or after reading chip info). To be able to do a pin reset when in debug mode you must set the RESET register to 1 as you did with JlinkExe.

If you don't want to use nrfjprog or JlinkExe to do that manually, you can enable it in the code. Just add NRF_POWER->RESET =1; in your code, you should be able to do pin reset after programming.

RE: Does nRFgo Studio 1.20.0 "release" the nRF51822 SWDIO pin to be used as a chip reset?

David Fritsch — Fri, 14 Aug 2015 17:21:09 GMT

Hi Hung,

Yes, "nrfjprog -p" essentially works to trigger a reset, after which the application resets of the Nordic work correctly. So, I can run my JLinkExe batch/script, or run "nrfjprog -p", to recover my Nordic reset line. Based on what you claim, however, I shouldn't have to do this.

I was using nRFTools (and nrfjprog.exe) version 7.5.0. I updated to version 7.5.2, but got the same results. This doesn't surprise me because the 7.5.0 version of nrfjprog worked when I manually ran it. That is why I was wondering if Studio 1.20.0 had a bug in which it wasn't performing a "nrfjprog -p", or its equivalent, before exiting. For me, previous versions of nRFgo Studio do not have this issue.

Just some further info: nRFgo Studio correctly identifies my Nordic as "nRF51822 CFACA00 (0x0087)". Also, I don't have to actually program the chip to have this issue. Running nRFgo Studio, selecting "nRF5x Programming" (and letting it connect & read chip info), and exiting, is enough.

RE: Does nRFgo Studio 1.20.0 "release" the nRF51822 SWDIO pin to be used as a chip reset?

Hung Bui — Fri, 14 Aug 2015 09:00:41 GMT

Hi David,

Which nRFTools version are you using ?

The nRFGo Studio relies on nrfjprog.exe tool to program/erase/reset the chip.

You can try trigger a reset via nrfjprog.exe tool with the -p or -r option.

I'm using nrfjprog v 7.5.2 (same version with nRFTools) and it resets the chip properly.