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
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