Generate 32768 hz signal on a GPIO

RE: Generate 32768 hz signal on a GPIO

Yashur — Thu, 02 Nov 2017 10:21:24 GMT

The RTC clock gives only half of it as the frequency as the frequency,that is 16.37KHz

RE: Generate 32768 hz signal on a GPIO

Florin — Tue, 24 Oct 2017 12:58:21 GMT

Hardware. I patched a wire from the crystal to the other chip.

RE: Generate 32768 hz signal on a GPIO

Yashur — Tue, 24 Oct 2017 12:51:17 GMT

Hi florin! I need a 32k clock for MAX30003 bio medical sensor too! But i'm measuring only 16.38Khz with the above code.Did you get a 32K signal from the above code? and how did you share the 32k signal from the crystal? It was a hardware sharing or a software sharing? Thank You!

RE: Generate 32768 hz signal on a GPIO

Florin — Tue, 24 Oct 2017 12:46:44 GMT

Hi Yashur, I used initially the code in the link above. I actually needed the signal for the Si4703 FM receiver and the signal provided via the GPIO although was oscillating correctly I suppose, introduced so much noise that it made tuning impossible. In the end I shared the 32k signal from the crystal and it worked perfectly.

RE: Generate 32768 hz signal on a GPIO

Yashur — Tue, 24 Oct 2017 12:12:36 GMT

Hey florin! May i know how did you manage to do it? Can you provide me with the basic code for LFCLK! Thank you!

RE: Generate 32768 hz signal on a GPIO

Florin — Thu, 16 Oct 2014 07:58:07 GMT

I have found the answer I was looking for here: devzone.nordicsemi.com/.../

Thanks for all suggestions! florin

RE: Generate 32768 hz signal on a GPIO

John — Wed, 15 Oct 2014 13:14:34 GMT

According to this answer, you can share the crystal:

Earlier answer

RE: Generate 32768 hz signal on a GPIO

Florin — Wed, 15 Oct 2014 04:42:51 GMT

Sure. I want to control another chip, a SI4703 that requires a 32kHz clock. I don't know if it's possible to share the same XTAL with the nRF51 though therefore an option is to generate this clock signal separately.

RE: Generate 32768 hz signal on a GPIO

wlgrd — Tue, 14 Oct 2014 21:57:01 GMT

Could you elaborate on the use case of this since you cannot use the crystal directly and need it out on GPIO?

RE: Generate 32768 hz signal on a GPIO

Nils Minor — Tue, 14 Oct 2014 21:42:27 GMT

Hi, why don't you use the RTC signal directly ?