ChibiOS Free Embedded RTOS

@hyOzd: What clock source are you using? Have you taken care of clock source tolerance/drift?

Uli

Writing is a really good way of thinking : ) I was writing a lengthy post about my issue then I realised the problem.

Note that I was having this problem with 10MHz setting. Timer clock is set to the 84MHz. It's not possible to get 10MHz from 84MHz with a simple pre-scaler :s

Here is some simple math. Measurement shows that `delay_us(50)` is `48,05us`. With 10MHz this means a counter value of `500`. But my timer freq. isn't actually 10MHz its;



In this case, `500` counter value will give me


If I add constant 0,4 us delay to this;



This is almost exactly the measured value.

Sorry for wasting your time I have no idea how I missed this because this was the first thing that came to my mind! I checked the timer clock but didn't see the issue

Hi,

Assertions should catch incorrect values, make sure to enable them (and other debug options) in chconf.h during development.

Giovanni

Thanks for tip. I'm certainly doing this!

But how do I access the runtime debug messages when assert is enabled? I can see the crash at call stack when debugging. But is there any other way?

If you use ChibiStudio (or Eclipse), the ChibiOS debug plugin can retrieve the error message for you.

Giovanni