Test the accuracy of external LFCLK.

RE: Test the accuracy of external LFCLK.

Sigurd — Mon, 17 Dec 2018 10:04:21 GMT

If I were to test this, I would have used an logic analyzer(e.g. from Saleae). Configured the RTC to generate a compare event after e.g. 100 seconds, then used PPI and connected the GPIOTE to toggle a GPIO together with the RTC START task (PPI fork), and GPIOTE to toggle the same GPIO on the RTC compare event. Then measured the time using the logic analyzer tool.

RE: Test the accuracy of external LFCLK.

victor_CHINA — Sat, 15 Dec 2018 07:26:51 GMT

The datasheet shows the accuracy of the external LF is 20ppm

So ，I am not sure wether my test result is trustworthy or not

RE: Test the accuracy of external LFCLK.

Sigurd — Fri, 14 Dec 2018 15:57:35 GMT

[quote userid="25672" url="~/f/nordic-q-a/41549/test-the-accuracy-of-external-lfclk"]so the accuracy of CFCLK is ≈ 100ppm[/quote]

Is this the accuracy you expected? What is the accuracy of the external LF crystal you are using?

RE: Test the accuracy of external LFCLK.

victor_CHINA — Fri, 14 Dec 2018 01:16:44 GMT

Hi owneil，I know that, thanks for your remind

RE: Test the accuracy of external LFCLK.

awneil — Thu, 13 Dec 2018 08:38:43 GMT

[quote userid="25672" url="~/f/nordic-q-a/41549/test-the-accuracy-of-external-lfclk"]Hi Dear nordic employee[/quote]

You realise that this is a public, user forum - not staffed purely by Nordic employees?

https://devzone.nordicsemi.com/backstage/f/welcome-to-the-devzone/30115/how-to-know-the-respondent-is-nordic-employee-or-not