How to reset a nRF52832 with only SWDIO and SWDCLK (not using a J-Link ruling out using "nrfjprog -p --family nrf52")

RE: How to reset a nRF52832 with only SWDIO and SWDCLK (not using a J-Link ruling out using "nrfjprog -p --family nrf52")

Kenneth — Sun, 13 Sep 2020 13:56:48 GMT

You may find this useful for additional information also:

https://infocenter.nordicsemi.com/topic/nwp_027/WP/nwp_027/intro.html

RE: How to reset a nRF52832 with only SWDIO and SWDCLK (not using a J-Link ruling out using "nrfjprog -p --family nrf52")

Nguyen Hoan Hoang — Thu, 10 Sep 2020 15:07:24 GMT

nrfjprog is for blink only. IDAP-Link has its own IDAPnRFProg for it.

RE: How to reset a nRF52832 with only SWDIO and SWDCLK (not using a J-Link ruling out using "nrfjprog -p --family nrf52")

Visti Andresen — Thu, 10 Sep 2020 14:42:06 GMT

How fast is IDAP-Link compared to a Segger Base interface?

A STLink V2 clone with https://github.com/x893/CMSIS-DAP takes 2x as long to flash (though openocd) compared to a Segger Base, which adds up over even few 10k flash cycles.

RE: How to reset a nRF52832 with only SWDIO and SWDCLK (not using a J-Link ruling out using "nrfjprog -p --family nrf52")

Visti Andresen — Thu, 10 Sep 2020 14:34:45 GMT

But isn't nrfjprog limited to exclusively working with Segger j-link compatible interfaces?

Also as mentioned "nrfjprog -p --family nrf52" resets the chip deep enough to disable debug interface.

I would however like to know how "nrfjprog -p --family nrf52" performs the reset, which registers does it write to, does it send a bit stream to the nRF52?

As a side note writing 1 to CTRL-AP->RESET does reduce the idle current indicating that the debugger circuitry has been disabled, but the nRF52 seem to be stuck in reset/never reboots.
And I have to power cycle the device to regain control of it.

RE: How to reset a nRF52832 with only SWDIO and SWDCLK (not using a J-Link ruling out using "nrfjprog -p --family nrf52")

Nguyen Hoan Hoang — Thu, 10 Sep 2020 14:12:09 GMT

The IDAP-Link does it fully automatic. It has software written specifically for parallel programming multiples boards for production purpose too. It handles programming of softdevice, app firmware and dfu with approtect activation.

RE: How to reset a nRF52832 with only SWDIO and SWDCLK (not using a J-Link ruling out using "nrfjprog -p --family nrf52")

Kenneth — Thu, 10 Sep 2020 10:46:48 GMT

Try nrfjprog --debugreset

RE: How to reset a nRF52832 with only SWDIO and SWDCLK (not using a J-Link ruling out using "nrfjprog -p --family nrf52")

Visti Andresen — Thu, 10 Sep 2020 07:14:13 GMT

Unfortunately the programmer is only connected using Vcc, GND (both not software controllable) and SWDIO and SWDCLK.

And while it would be possible for a human to disconnect power or push buttons a fully automated approach is desired.
(And possible since a JLink can pull it of, only the "protocol" eludes me)

RE: How to reset a nRF52832 with only SWDIO and SWDCLK (not using a J-Link ruling out using "nrfjprog -p --family nrf52")

Nguyen Hoan Hoang — Wed, 09 Sep 2020 20:30:32 GMT

I power cycle will acheive the same result for enabling APPROTECT. You can use OpenOCD for that too. Reset using SWD is a debugger soft-reset command. Alternatively the IDAP-Link CMSIS-DAP can also be used in place of the STLink. It is designed for handling nRF51 &nRF52. You can soft-reset with a press of a button or just issue a protect command which will both set the APPROTECT and reset.