How do I properly setup my Timer2 to make it fire off every 5 secs?

RE: How do I properly setup my Timer2 to make it fire off every 5 secs?

Mitch996 — Fri, 05 Jan 2018 07:42:06 GMT

No inconvenience at all! Haha.

RE: How do I properly setup my Timer2 to make it fire off every 5 secs?

Jørgen Holmefjord — Thu, 04 Jan 2018 07:42:31 GMT

There is some delays as many people have been away for the holidays. Hopefully this will normalize quite soon. Sorry for the inconvenience.

RE: How do I properly setup my Timer2 to make it fire off every 5 secs?

Mitch996 — Thu, 04 Jan 2018 01:51:56 GMT

That's exactly the answer! Thank you!

Also, the answers seem to be kind of slow these days... what is going on? People are busy?

RE: How do I properly setup my Timer2 to make it fire off every 5 secs?

Jørgen Holmefjord — Wed, 03 Jan 2018 13:08:03 GMT

Hi,

Is this on nRF51 series? Note that TIMER1/2 on nRF51 series is only 16-bit timers. If you run the timer at maximum frequency, the timer will overflow after ~4 ms:

(1/16 MHz)*(2^16) = 4.096 ms

You need to change the prescaler, to slow down the timer. Unfortunately, the maximum prescaler value is 9, which will make the timer overflow at ~2 seconds:

(1/(16 MHz/(2^9))) * (2^16) = 2.097152 s

This means you can't achieve your desired 5 seconds using TIMER2 (on nRF51).

Anyway, I would recommend that you use RTC for such long timing, it runs on LF clock and will consume less current. See this post about difference between timers and RTC.

Best regards,

Jørgen