nRF51822 SPI frequency fine tune

RE: nRF51822 SPI frequency fine tune

Stephen — Fri, 04 Dec 2015 20:36:31 GMT

Frank- Just wondering if you ever figured this out. Were you able to create a clock using the SPI, at least at the fixed frequencies specified? Or did you revert to using a timer with the CC being auto-cleared by the short functionality, so you could generate your own specific clock? I am running out of timers in my system, and if I could free one up generating a clock with the SPI, it would really help me out.

RE: nRF51822 SPI frequency fine tune

Matt Leising — Wed, 18 Jun 2014 14:58:55 GMT

Just to be sure, 125 kbps rate in SPI would be driven by a 125 kHz clock then right?

RE: nRF51822 SPI frequency fine tune

Frank Zhao — Fri, 20 Sep 2013 20:24:28 GMT

even a timer is too slow, I can't write to the compare register fast enough, even with assembly

RE: nRF51822 SPI frequency fine tune

ovrebekk — Thu, 19 Sep 2013 12:53:13 GMT

Hung is right. If you just want to generate a clock signal of a certain frequency you should probably use a timer and the GPIOTE instead, that will give you much more flexibility.

RE: nRF51822 SPI frequency fine tune

Hung Bui — Thu, 19 Sep 2013 11:02:03 GMT

The FREQUENCY register actually is a single byte register, the options are fixed and you can't tweak it to get different bit rates.