NRF 52 Custom Board HRM Peripheral issue

RE: NRF 52 Custom Board HRM Peripheral issue

Pradeep — Sat, 03 Dec 2016 10:53:40 GMT

We assembled a new board and HRM sample has started to work with NRF Connect Mobile app. Not sure where the problem was, Thanks for your assistance.

But, the HRM service seems to get stuck at 220 bpm on the nRF Toolbox mobile App. Once this happens, the custom board is not discoverable and i have to take the battery out, put it back again to make the custom board discoverable.

I will start a new thread for this issue.

Thanks.

RE: NRF 52 Custom Board HRM Peripheral issue

bjorn-spockeli — Fri, 02 Dec 2016 12:23:46 GMT

Ok, then the LFCLKSRC settings hould be fine. No, you can use a PCB trace antenna( typically Quarter wave-length or meandered) or a chip antenna. I suggest that you take a look at the nRF52 Solar Beacon Design and the nRF52 DK design.

RE: NRF 52 Custom Board HRM Peripheral issue

Pradeep — Fri, 02 Dec 2016 11:43:25 GMT

Q1: Thanks for your reply. Now I understand the working of LED status indicators.

Q2: Custom board is using an external crystal.

Is there any particular make of antenna that has to be used in this design? Please advice.

RE: NRF 52 Custom Board HRM Peripheral issue

bjorn-spockeli — Thu, 01 Dec 2016 10:07:34 GMT

Q1: The SDK examples uses the Board Support Package(BSP) to indicate the status of the device. The HRM example will indicate that its in an advertising stage(BSP_INDICATE_ADVERTISING ) by blinking LED 1. You can find the list on this Infocenter page. The blinky example(found under examples\peripheral\blinky) will just flash its LEDs and does not use BSP as it does not use the SoftDevice.

Q2: Does your custom board have an external 32kHz crystal? If not, If it does not then you have to modify the NRF_CLOCK_LFCLKSRC in ble_stack_init() so that it uses the internal LF RC clock instead, i.e.

#define NRF_CLOCK_LFCLKSRC      {.source        = NRF_CLOCK_LF_SRC_RC,            \
                             .rc_ctiv       = 16,                                \
                             .rc_temp_ctiv  = 2,                                \
                             .xtal_accuracy = 0}

Best regards

Bjørn

RE: NRF 52 Custom Board HRM Peripheral issue

Pradeep — Wed, 30 Nov 2016 17:37:35 GMT

yes P.20 is the pin for LED on custom board and on the dev kit board. The Blinky sample when flashed to custom board, LED at P.20 is blinking.

RE: NRF 52 Custom Board HRM Peripheral issue

vist — Wed, 30 Nov 2016 16:05:21 GMT

Have you verified that the gpio pins to the leds are the same on your custom board as on the dev kit and compared the files in the examples/bsp folder?