SDK 12.3.0 - Using central ble_app_uart_c example with a custom board with nRF51822 - Can't initialize softdevice

[JFGagnon]

Hello,

we made a custom board using the chip nRF51822 and were able to use the template project in \..\examples\peripheral\template_project to make a button switch the led color on the board. So we know that the custom board is somewhat functionnal (we can erase/readback/write the chip).

What we are trying to do right now is load the example \..\examples\ble_central\ble_app_uart_c and \..\examples\ble_peripheral\ble_app_uart on two different board to see if we can create a communication between the two boards (and validating the antenna design).

However, when I try to load the project \..\examples\ble_central\ble_app_uart_c, with profile pca10028_s130 into the custom board, the softdevice initialization crashes.

Our setup is as follow: 

* Debugger : Segger Flasher Arm
* IDE : IAR 8.40.1
* SoftDevice : S130 2.0.1
*SDK : 12.3.0 (this version was selected for unknown reason to me, but the project should still be compatible)
* chip : nRF51822

The first thing I did is to use nRFgo Studio to flash softdevice S130 v2.0.1 into the chip and made a readback. This is what I get :

So I know that the right SoftDevice is programmed onto the chip.

Then, I tried to place a breakpoint after the ble_stack_init(); function, but the breakpoint in never reached. So I stepped into the code, and the line that is causing the issue is SOFTDEVICE_HANDLER_INIT(&clock_lf_cfg, NULL);

When running this line, the application crashes, but I am not able to go to app_error_handler, which should at least provide some information. When I run the application with breakpoints only in app_error_handler() , I still never get to the error.

I am not sure what I need to do to make the example run on the nRF51822 as opposed to the devkit (nrf51-DK) with the nRF51422 as they should have the same pinout and functionnality, with only the softdevice version supported being different.

Any hints on where to go from here would be appreciated.

Thanks

[JFGagnon]

I would like to add that we used the same crystal hardware as the devkit for our custom board (since SOFTDEVICE_HANDLER_INIT() uses the crystal to initialize). 

[Hung Bui]

Hi JFGagnon, 

Could you please send the schematics of your board ? 
Please try to test setting the clock_lf_cfg (NRF_CLOCK_LFCLKSRC) to use NRF_CLOCK_LF_SRC_RC instead of NRF_CLOCK_LF_SRC_XTAL as default. 

[JFGagnon]

Hello, I cannot share the schematics as they are confidential. However, changing the clock to SRC_RC instead of SRC_XTAL stopped the softdevice from crashing. We will use that for now and review our design later. Thanks for your help.