nRF52840 PDK to external board programming

RE: nRF52840 PDK to external board programming

Vijay — Tue, 12 Jun 2018 19:00:49 GMT

I have two custom boards and both of them draw approx. 95 mA when supplied 3.3 V. The board was designed with the reference schematic in mind. Can the programmer IC draw that much current?

-vivenkat

RE: nRF52840 PDK to external board programming

Håkon Alseth — Tue, 12 Jun 2018 18:40:12 GMT

Did you reverse the polarity? 94 mA is very high. It should draw a couple of milliamps when the chip is blank.

I'd recommend that you check the connections and look for shorts on your external board.

RE: nRF52840 PDK to external board programming

Vijay — Tue, 12 Jun 2018 18:08:27 GMT

"When shorting VTG->VDD_NRF (or pin VDD), you tell the board to use P20 as the target debug. Your external board, connected to P20 (1x8 header), should still be powered" - where should this command be given ?

On my DC power supply, the current reading is around 94 mA. I have a pca10040 Atmel IC and I am using it to program a nRF52810. The display on my JLink commander and nRFgo studio is the same what Labuka posted.

Thanks very much for your reply!

-vivenkat

RE: nRF52840 PDK to external board programming

Håkon Alseth — Tue, 12 Jun 2018 14:00:03 GMT

Could you check the current consumption of your external board?

You haven't cut SB9 on a previous occasion and not remembered to place a jumper cable on the "nRF current measurement" header?

Best regards,

Håkon

RE: nRF52840 PDK to external board programming

Labuka — Tue, 12 Jun 2018 10:26:30 GMT

Hi,

I gave the connections exactly as you described but still I'm facing the same issues. I'll post the logs for reference.

RE: nRF52840 PDK to external board programming

Håkon Alseth — Tue, 12 Jun 2018 09:25:34 GMT

Hi,

If we short the VDD_nRF and VTG pins, where should the custom boards' VDD be connected? Should the board be powered separately?

When shorting VTG->VDD_NRF (or pin VDD), you tell the board to use P20 as the target debug. Your external board, connected to P20 (1x8 header), should still be powered. I recommend powering your external board with either "VDD" or "VDD_NRF" from the nRF5x-DK. This is to ensure that the voltage is equal on both the debugger and your custom board.

If you still have issues connecting to your board, please check with both nrfjprog and JLink Commander and post logs from both programs.

Best regards,

Håkon

RE: nRF52840 PDK to external board programming

Vijay — Mon, 11 Jun 2018 19:05:20 GMT

If we short the VDD_nRF and VTG pins, where should the custom boards' VDD be connected? Should the board be powered separately?

Thanks

-vivenkat

Edit 1: My connections are as follows:

On P20,
VDD_nRF and VTG are shorted
VDD is used to power the custom Nordic board

SWDIO and SWDCLK in nRF52 DK to SWDIO and SWDCLK on the custom Nordic board

One of the GND pins from the DK to the custom board.

I have the same error as Labuka. Any help would be gladly appreciated!

-vivenkat

RE: nRF52840 PDK to external board programming

Håkon Alseth — Tue, 05 Jun 2018 11:20:56 GMT

Hi,

It is recommended that you short "VDD_NRF" to "VTG" on P20, to force the segger to use this port for programming, and power your external board from the nRF5x-DK.

Once this is done, you can connect SWDIO+SWDCLK to your target, in addition to the VDD_NRF and GND.

What does the output of Jlink Commander show if you try to connect using this tool?

Do you have other custom boards that behave similar?

Best regards,

Håkon

RE: nRF52840 PDK to external board programming

Labuka — Mon, 04 Jun 2018 12:08:37 GMT

I tried using nRFjprog but still that didn't work out. I thought I might have locked out the chip so tried recovery but that also didn't work out. Is there any way to work it out?

RE: nRF52840 PDK to external board programming

ketiljo — Wed, 23 May 2018 12:27:12 GMT

VDD should be connected to VTG

Use nRFjprog instead, install the latest version of nRF5x command line tools.

RE: nRF52840 PDK to external board programming

Labuka — Wed, 23 May 2018 12:01:06 GMT

Yes, the external board is powered by a 3.3v source. So where should I connect the VDD from my external board to nRF52 PDK?

RE: nRF52840 PDK to external board programming

ketiljo — Wed, 23 May 2018 11:41:55 GMT

Is the external board powered? The nRF52 PDK does not supply power via VTG so you must supply the board externally. VTG is input to the reference voltage of the level shifters on the nRF52 PDK.