Weird behavior: Simply changing loop counter variable from uint16_t to volatile uint16_t causes initial delay (with variable delay = 0) going from ~500 ns to ~120 us
The code is uint16_t delay; select_function(); for(delay = 0; delay < transfer->dev->afterstart; delay++); Any ideas? El mié, 24 mar 2021 a las 12:21, Gregory Nutt (<spudan...@gmail.com>) escribió: > > > What I'm trying to do is to generate hold and disable times for SPI CS, > > which should be about 50 ns > That resolution is too high for any system timer. > > I started by an empty for loop but it seems optimization gets rid of it > (I > > haven't researched the issue properly). Then I thought a proper function > > would be better but got stuck in that expression "sleep resolution" > > Add volatile to the loop counter variable and the optimizer will not > remove it. > > >
