Using nRF52840 DK to program a second nRF52840 SoC

[HSh]

Hello,

I have an nRF52840 chip (Holyiot nRF52840 module) and I want to program the chip using an nRF52840 DK. The Holyiot module is basically an nRF52840 mounted on a PCB.

https://www.aliexpress.com/item/holyiot-18010-Nordic-nRF52840-module-Bluetooth-low-energy-development-board-for-BLE-mesh-bluetooth-5/32868002366.html

So, I connected the following pins to P20 connector of nRF52840 DK and tried to program with nRFgo Studio. Although I am able to program nRF52840 DK itself, I am not able to program the second device.

1. P20. 1 (VDD_nRF) to V_nRF. In Holyiot, this is VDD/VDDH.

2. P20. 3 (SH_VTG) to V_nRF.

3. P20. 4 (SH_SWDIO) to SWDIO

4. P20. 5 (SH_SWCLK) to SWCLK

5. P20. 8 (SH_GND_DETECT) to GND.

5. P1. GND to GND (three GND pins on Holyiot).

The above setting did not work, I also connected VBUS to GND, no change.

Can you please help me find the problem?

Thanks

[haakonsh]

I've got my hands on the Holyiot module, I'll see if I can reproduce your issue. 

Update:

I had no problem connecting to the holyiot module. Most likely you forgot to cut SB40 or use the wrong pin mapping. 

I powered the module from a bench top power supply at 3V. On the DK I cut the power supply to the on-board nRF52840 by cutting SB40, connected VTG to DK-VDD and GND Detect to DK-GND. I then connected SWDIO and SWDCLK.

After connecting the DK to my computer and powering the holyiot module I ran 'nrfjprog -f nrf52 -e' and successfully erased the module. 

 

[David Fogelsong]

That may be the problem that he's having.  On some new modules you need to erase them first to remove the write protection.  After that, you don't need to anymore.

[HSh]

Hi, thank you for your time. I didn't cut SB40 as it is not mentioned here:

http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52%2Fdita%2Fnrf52%2Fdevelopment%2Fnrf52840_pdk%2Fhw_debug_out.html

I taught when detecting power on VTG, the onboard chip-set will no longer work and JLink is only used for the second device. I will try this too.

[HSh]

The nRFGo Studio suggests to erase/recover or something like that. However, this does not work either.

[David Fogelsong]

I just recently successfully programmed an nRF52840 module using the nRF52840-DK: with the two connected all I had to do was drag the .hex file to the JLINK "drive" as usual, and the external module got programmed.  Maybe try that?

[HSh]

Thanks @haakonsh.  Cutting SB40 indeed worked and I am now able to program the holyiot. Next step is to program with a BLE DFU. David Fogelsong Any experience/suggestions?