Hi Albert,
Am 24.01.2011 12:58, schrieb Albert ARIBAUD:
Hi Andreas,
Le 24/01/2011 09:25, Andreas Bießmann a écrit :
That's where I come back to one point of my proposal: if we can get a general framework for get_timer() to return a 64-bit free-running tick value, then we might not need a ms-based get_time() at all, because we could use get_timer() as well for ms timings, provided we can convert our timeout from ms to ticks, i.e.
/* let's wait 200 milliseconds */ /* Timing loop uses ticks: convert 200 ms to 'timeout' ticks */ timeout = ms_to_ticks(200); u32 start = get_timer(); /* start time, in ticks */ do { ... } while ( (get_timer() -start)< timeout);You may think about the following change to this proposal:
/* lets wait 200 ms */ /* get the end point of our timeout in ticks */ u64 timeout_end = get_timer() + ms_to_ticks(200); do { ... } while ( get_timer()< timeout_end);
The problem here is that in the loop exit condition you replace a difference between two unsigned times (which always yields the correct duration) with a comparison of two dates (which does not).
Ok, I got your point.
regards
Andreas Bießmann