Unable to program a blank nrf52840

RE: Unable to program a blank nrf52840

FrancoisG — Mon, 21 Nov 2022 13:51:36 GMT

I ended up using a nRF52840 DK 3.0.0 with SB19 bridged which does allow following the target voltage without changing anything else.

However in my specific case, my problem was an issue with the soldering of the module.

Once the soldering issue resolved, programming with the DK (with bridged SB19) works but also is my intended programming setup thought MAX32625PICO + pyocd.

RE: Unable to program a blank nrf52840

FrancoisG — Mon, 03 Oct 2022 16:37:08 GMT

Thank you very much I will try that.

RE: Unable to program a blank nrf52840

Jørgen Holmefjord — Mon, 03 Oct 2022 15:33:49 GMT

Do you mean if the DK can program a target running at 1.8V supply voltage?

It should be possible if you get a nRF52840 DK. With the default configuration and wiring (powered through the J2 interface MCU USB port), the DK will be power by 3.0V from a regulator on the board. If you power the board through the nRF_USB (J3), and set the nRF Power Source switch (SW9) to USB, the board will be powered by the voltage controlled by REGOUT0. If this register is set to 1.8V, the debug chip on the DK will also run at 1.8V, and SWD pins will use this voltage, and allow programming of external boards running off other voltage levels. See Power supply for more details about the power supply modes on the DK.

This is a logic trace of the SWD pins on P20 with above configuration/wiring:

Best regards,
Jørgen

RE: Unable to program a blank nrf52840

FrancoisG — Mon, 03 Oct 2022 13:52:10 GMT

Hi,

I don’t mind getting an nRF DK but will it work? I see online that it doesn’t work at 1.8v.

RE: Unable to program a blank nrf52840

Jørgen Holmefjord — Mon, 03 Oct 2022 13:49:16 GMT

Hi,

We do not support programming through OpenOCD.

You should get a J-Link debugger (or a nRF5x DK), to check if you are able to program your module correctly.

I will leave the thread open in case someone in the community knows what causes the issue you are seeing and can help you out.

Best regards,
Jørgen

RE: Unable to program a blank nrf52840

FrancoisG — Sun, 02 Oct 2022 15:21:48 GMT

This is a random capture of the SWDIO signal probed on the 2x5pin connector on the breakout board:

Just to get an idea of the signal integrity I'm dealing with.