Programming custom NRF52832 board using SWD interface

[DineshB]

Hello NRF,

I have a custom board with NRF52832, and exposed the SWDIO, SWDCLK, GND, VDD, RESET pins for programming the board through the NRF52-DK board.

I started with a sample peripheral_uart, connected the NRF52-DK board to my PC, and managed to BUILD and RUN the sample application.

I verified that the app is working, by connecting to the UART service advertised by this app (on NRF52-DK) through another device that has NRF-TOOLBOX and used the UART service to query the NRF UART (NRF52-DK board) and managed to read write and verified the same over the console.

Now, I want to program my custom board, instead of the NRF52-DK board. Based on some suggestions on this site, I connected the

NRF52-DK        CUSTOM_BOARD

SWDIO             SWDIO

SWDCLK          SWDCLK

GND-DET         GND

VTG                 VDD/3V3

I then powered my board and then tried the BUILD and RUN option on the SEGGER.

It seems like my custom board is not getting programmed.

I would like to know : 

1. Do I have to first program a bootloader on to my custom board. If so, please advise a boot loader that I can download from your site (if possible) and the steps to program the same on to my custom board.

2. How to program the compiled/build binary/hex files on to my custom card? Just BUILD and RUN would download the binary on to the connected custom board, instead of the NRF52-DK board? (because my custom board is connected through the SWD port and GND detected?) If BUILD and RUN wouldn't work, where can I find the compiled binary or hex file where I can program the same on to the custom board , perhaps by using command line nrfjprog tool???

3. I believe the peripheral_uart has it's pin definitions, for the RX, TX, LEDs etc. Since my custom board pin assignments might be different from that of the NRF52-DK, where can I find these definitions, so I can go map the pins?

All I need is to demonstrate this peripheral_uart app on my custom nrf52832 board, where I will connect a serial port on to its RX/TX to a putty terminal (on my pc) and then able to rx/tx data back and forth with the other connected device (NRF toolbox -> UART).

I appreciate your help in this regard.

regards,

Dinesh.

[Simonr]

Hi Dinesh

Please confirm that your custom device is connected as shown in this picture when trying to program it. How is your custom board powered?

1. No, you do not need a bootloader, the debugger on the DK will be able to access the Flash of the nRF52 series through the SWD interface.

2. Yes, when the custom board is connected correctly to the DK, the "Build and Run" command in SES will download the application onto the custom board, as it will detect connected custom boards automatically.

3. In the peripheral_uart example you can see that the RX and TX pin numbers are defined as RX_PIN_NUMBER and TX_PIN_NUMBER. These are defined in the board file (C:\...\nRF5_SDK_17.0.2_d674dde\components\boards\pca10040.h), and when making a project for a custom board, you should create your own custom_board.h file. This is described in the Infocenter here where it is explained how to use the SDK with custom boards.

Best regards,

Simon

[DineshB]

Hello Simonr,

I was powering my custom board separately (through a coin cell battery) and wired the VTG on DK to VDD on my board side (3.3v).

I will remove the power source (coin cell) on my board, and power the custom board through the NRF52-DK as per your suggestion.

I believe, once I execute the BUILD  & RUN, the same behavior is expected on my custom board, similar to how it runs on the DK, as on DK, I see the NRF advertisements, but when I programmed my board, I couldn't see the advertisements.

I will test this and get back to you.

Thanks.

regards,

Dinesh.

[Simonr]

Please let me know whether this is successful or not. If you're still struggling, please let me know some details about your custom board. If you're, for example, lacking an external LF crystal that is likely the issue.

Best regards,

Simon