nRF52840 programming

[Jagbir]

Hi,

I am using nRF52840-DK with Segger Embedded Studio . In this dev kit the Atmel chip ATSAM3U2CA-AU provides the programming/debugging  interface. In order to save BOM cost I do not want this chip on my product board. Are there any commercially available boards which can provide the programming/debugging interface externally.

Thanks.

[ketiljo]

As others say, you don't need the Atmel chip on your board. Only a connection to the SWD interface is needed. So break out SWDIO, SWCLK, GND and VDD to a suitable connector, for instance a 10 pin J-link connector, 6 pin needle adaptor or whatever you like. Then use a JLink programmer or the DK you already have

[Jagbir]

I was able to program this nRF52840-DK using another nRF52840-DK . However, I am still unable to program this DK using a Segger J-link plus. I have checked my cable connection again, they seem to be fine. I have also tried an external pull up on SDIO but still it does not work.

[ketiljo]

Make sure the J-link have the latest firmware. SDIO is not used for programming. You need VDD from the board to be programmed to the J-Link as well, to make sure the J-link detects the boards. What error message do you get?