NRF51822 mKit P0.26 problems

RE: NRF51822 mKit P0.26 problems

simonk — Tue, 26 Jan 2016 14:03:04 GMT

Well, internal pull-up resistor on P0.26 is a working solution for my problem. Many thanks to all for help.

RE: NRF51822 mKit P0.26 problems

RK — Tue, 26 Jan 2016 13:31:22 GMT

it will - so that's not the problem

RE: NRF51822 mKit P0.26 problems

simonk — Tue, 26 Jan 2016 13:27:46 GMT

If I select CLOCK_LFCLKSRC_SRC_RC and touch P0.26 with my fingertip, clock stops... I thought, that RC/Synth option would disconnect that pin from clock generation completely.

RE: NRF51822 mKit P0.26 problems

RK — Tue, 26 Jan 2016 13:05:58 GMT

what do you mean 'These options are not ok'. You want to select one of the RC ones if you don't have a 32768Hz crystal.

RE: NRF51822 mKit P0.26 problems

simonk — Tue, 26 Jan 2016 13:02:53 GMT

I have found Clock source settings in nrf51_bitfields.h

CLOCK_LFCLKSRC_SRC_RC /*!< Internal 32KiHz RC oscillator. / CLOCK_LFCLKSRC_SRC_Xtal /!< External 32KiHz crystal. / CLOCK_LFCLKSRC_SRC_Synth /!< Internal 32KiHz synthesizer from HFCLK system clock. */

If I select RC or Synth in SOFTDEVICE_HANDLER_INIT, those options are not ok... Since I wan't GPIO on that pin, external Xtal option is not possible. Any other suggestions? Or am I doing something wrong?

RE: NRF51822 mKit P0.26 problems

simonk — Tue, 26 Jan 2016 09:23:08 GMT

I am working with SDK in uVision.

If I am correct, this clock source is set within this call when I initialize Bluetooth stack. But I cannot change this to any other source, except low power ones.. SOFTDEVICE_HANDLER_INIT(NRF_CLOCK_LFCLKSRC_RC_250_PPM_4000MS_CALIBRATION , false);

RE: NRF51822 mKit P0.26 problems

Eirik Midttun — Tue, 26 Jan 2016 09:16:38 GMT

Are you developing with SDK, mbed2 or mbed3?

RE: NRF51822 mKit P0.26 problems

RK — Tue, 26 Jan 2016 09:10:19 GMT

you set it when you enable the softdevice, it's the clock parameter. Use any one of the RC corrected ones, just don't use the LF crystal one

RE: NRF51822 mKit P0.26 problems

simonk — Tue, 26 Jan 2016 09:08:54 GMT

I am using softdevice S130. Which clock setting would then be ok and how to select it?

RE: NRF51822 mKit P0.26 problems

Eirik Midttun — Tue, 26 Jan 2016 08:58:43 GMT

Well, the only special thing about these IOs is that they are connected to the 32k crystal. So if the cut the connection the the crystal and still use it as a clock source it sounds like there will be clock issues. Check if it helps to changes the clock settings.

RE: NRF51822 mKit P0.26 problems

RK — Tue, 26 Jan 2016 08:54:19 GMT

Did you make sure none of the software running is trying to use the crystal which you now don't have connected to the pins? I would think if anything tried to start the LF clock using those pins and you touched them, chip probably wouldn't like it too much.