Error programming mbedOS application on custom nRF52 board with nRF52-DK using DAPLINK

[MTomoum]

The problem is I can't figure out a way to use the shield pins on the board (P20) to program an external MCU (nrf52832). It just refuses to do so it always programs the onboard chip. I even tried shorting SB32 and it didn't work. I am using mbed studio to develop and debug.  

 

Things I tried:

1. I tried connecting my mcu directly to the SWD trace connected onboard. I soldered to the nets on P18 and then cut power to the onboard MCU from SB9.  

My Setup:

Hardware: nrf52-DK Version 2.1.0

Interface MCU firmware: 0253_sam3u2c_mkit_dk_dongle_nrf5x_0x5000.bin

[Marjeris Romero]

Hi,

The easiest is to use the Debug out connector (P19) of the nRF52 DK directly and a 10-pin cortex debug connector cable: https://infocenter.nordicsemi.com/topic/ug_nrf52832_dk/UG/nrf52_DK/hw_debug_out.html

The connections in the figure you posted look OK as well.

But you also need to remember to power your external board with the voltage supported by the nRF52 DK for external debugging, which is 3.0V.

Best regards,

Marjeris

[MTomoum]

Hey Marjeris,

Thanks for your suggestion. I have indeed tried to use p19 but I used the nrf VDD to power my board instead of an external supply but it didn't work.

Anyways, Ive decided to abandon mbed OS and just go with using the SDK. The main reason I wanted to go with mbed is its natively in C++ and easily being able to switch to other chips by simply changing the target. Also nRF SDK does not play nice with C++. Oh well back to C...  

Best,

Muhab

[Marjeris Romero]

MTomoum said:

I have indeed tried to use p19 but I used the nrf VDD to power my board instead of an external supply but it didn't work.

Have you measure what output voltage are you getting from VDD pin on P19?

MTomoum said:

Anyways, Ive decided to abandon mbed OS and just go with using the SDK

That's OK. If you need support for working with the nRF5 SDK or the nRF Connect SDK (NCS) you can create a new ticket here in Devzone. We don't offer technical support for mbedOS so it's better to use one of Nordic's SDK if you want help with your project.

Best regards,

Marjeris