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 again Dinesh

You're using nRFConnect SDK (NCS), correct? And thus this example project? If you only have the one external crystal that explains why it doesn't start advertising. In order to run most of our examples, you also need to use a LF clock (32.768 kHz), and our example projects are configured to use the optional external (XTAL) 32.768kHz crystal. You can configure the example to use the internal RC oscillator instead though, which should make the application run as intended.

1. NCS does not use the SoftDevices, so it seems like you're mixing up the nRF5 SDK and the nRFConnect SDK.

2. I believe it should be sufficient to configure the project to use the RC oscillator instead of the XTAL. Please see the documentation here for details. The calibration should be enabled by default when the RC oscillator is enabled it seems.

Best regards,

Simon

[DineshB]

Hello Simon,

I managed to program the Sparkfun dev board and get it up and running.

What I had to do was to select nrf52_sparkfun as the Board Name, instead of nrf52dk_nrf52832.

nRF Connect -> Tool Chain Manager ->  nRF Connect SDK v1.4.2 -> Open IDE

Then I use,

File -> Open nRF Connect SDK project -> fade led (projects) , nrf52_Sparkfun (Board Name) , 1.4.2 (nRF Connect SDK Release), 1.4.2 (nRF connect Tool chain version)

So, on the Sparkfun dev kit, nothing is connected, all GPIOs are open, only the rx/tx are connected to a serial2uart cable. Their definitions are, P0.27 -> TX and P0.26 -> RX

I still don't understand, if the circuit is not connected to any other peripheral, what would be the different settings in terms of selecting the Board (nrf52DK vs nrf52_sparkfun) that makes the board work only when you select the nrf52_sparkfun?

Next, I will try to program my custom board with nrf52_sparkfun as the Board selected. But this still puzzles me, what would prevent the app (uart_peripheral) work only with the nrf52_sparkfun Board selection, instead of the nrf52DK.

regards,

Dinesh.