Custom NRF52810 board not advertising and hanging on nrf_sdh_enable_request()

[epice500]

Hello all,

I have recently developed a custom board that uses an nrf52810. It also contains an accelerometer as well as some hardware for regulating the voltage and charging a battery. The issue I am having is that the device is unable to advertise. I have been searching around the internet for days however have been unable to find a solution to my problem. I am using sdk17.1.0 and softdevice s112 v7.2.0. I have been trying to use the ble_blinky_pca10040e example to help me start learning to develop for this board. My board does not contain a LF clock and therefore I set it to use the RC in the sdk_config. I have also set the ram and flash sizes appropriately. I have made numerous other modifications to the sdk_config however nothing appears to work. I at first used rtt viewer to see the logs from the device while it ran and it would sometimes throw errors while attempting to set BLE_CONN_CFG_GAP, BLE_GAP_CFG_ROLE_COUNT, etc, sometimes with a fatal error thrown as well. I started using SES to debug the application. When the program is loaded onto the device it runs until it hits ble_stack_init and then either halts on the register at 00000A60, or (more often) gets stuck on the line SVCALL(SD_SOFTDEVICE_ENABLE, uint32_t, sd_softdevice_enable(nrf_clock_lf_cfg_t const * p_clock_lf_cfg, nrf_fault_handler_t fault_handler));. The errors commented above the call make me think that it has something to do with the LF clock config however if I check the configuration it is correct. (set to RC, accuracy to 1, RC_CTIV 16, RC_TEMP_CTIV to 2), and I can also see the correct values in the variable when debugging. The device is able to run examples that do not involve BLE (like the blinky example) without issue. This is my first time taking on a project this large and I will admit at this point I am feeling rather lost. Any assistance is greatly appreciated. I am also happy to upload any code or hardware files should anyone require them. 

Thank you!

[Jared]

Hi,

Looking at your design I see several points that should be addressed:

1. DEC4 is not connected to anything
2. What is the circuit on P0.25 and P0.28 doing? 
3. The antenna path does not follow the reference design. The antenna path should consist of two parts. The first part is the matching network for the radio which should be a 0.8 pF parallel capacitor and a 3.9 nH series inductor as shown in the reference design below. In addition to this you'll need a matching network for your antenna. I checked the datasheet of the chip antenna that you're using and it specifies a parallel capacitor and a series inductor seen from the antenna. This should be added in series to the matching network of the radio.

The application shouldn't assert even though you haven't added the matching network. That is probably related to my DEC 4 comment above. But you have a good signal without a matching network for the antenna. You also have to do a antenna tuning at some point.

Looking at your PCB design, It seems the GND layer is missing?

regards

Jared