AnsweredAssumed Answered

STM32F405 - measure two frequencies >= 10MHz

Question asked by michael on Jan 27, 2014
Latest reply on Feb 10, 2014 by sung.chen_chung
Hey at all,

First of all I want to say that my english isn't the best.
I have got a new project to do it on a STM32F405 controller.

I must measure two frequencies:
1. f1 = 13 to 16MHz
2. f2 = 10 to 13MHz

my plan to do it is:
 - create a internal time base 0.1ms
 - count at two input pins the edge of the two external frequencies,
 - and calculate it.

So what is the best way to do it on STM32? I read something with master and slave timers. ?!?
Further I want to do it in the peripherals to hold the cpu work very low.

the next step is to save the calculated frequencies in two ring buffers. because i have to make a filter over some samples to get the correct value.
what ist the best way to implement a ring buffer?

I hope somebody can give me some tips, especially for the different timers.

BR michael.