JLink able to connect but not able to flash

RE: JLink able to connect but not able to flash

Vidar Berg — Mon, 16 Aug 2021 06:51:35 GMT

Thanks for confirming. Have you tried to lower the programming speed as well? That may be neccesarry if you have long programming cables.

e.g.

nrfjprog -c 125 --recover // 125 KHz SWD clock speed

RE: JLink able to connect but not able to flash

EarthLord — Fri, 13 Aug 2021 08:02:06 GMT

Any updates on this? Thanks.

RE: JLink able to connect but not able to flash

EarthLord — Sat, 07 Aug 2021 14:19:11 GMT

The supply on the custom board is 3.3V and we've verified this. And on the DK, we've shorted Vtg to VDD for it to program the external board. I see that with this the VDD of nRF DK is lower but still within the 0.7VDD of 3.3V.

RE: JLink able to connect but not able to flash

Vidar Berg — Fri, 06 Aug 2021 15:16:58 GMT

Hello,

Are you supplying your target board with the same VDD voltage as the nRF52840 DK has? Please note that the On-board J-link debugger does not have a built-in level shifter so the voltage must be the same on both boards as noted here: Debug output