> > you don't have to worry about reload jitter that can happen when
> > loading the timer low byte with non-zero values

> Are you sure there is no jitter if you reset the upper byte only?

AFAIK jitter affects just the lower byte. If the timer/counter is
free-running and you're looking at and reloading just the upper byte
then the lower byte is irrelevant for detection (eg IRQ) purposes

Jitter aside, from 7.5.1

"For writes, it is recommended that the user simply stop
the timer and write the desired values. A write contention
may occur by writing to the timer registers while the register
is incrementing. This may produce an unpredictable value in
the timer register"

I infer from this that only a register that is incrementing could be
corrupted, which leads me to conclude that if the low byte is
incrementing untouched by s/w and you're reloading the upper
byte at a time when it can't be incrementing, then that contention
corruption shouldn't (can't ?) cause any problems

> But it remains accurate over the long term

Yes, exactly. Nothing to get upset about if a cycles-based timer is a
second or two out after a few hours. At 24 hours it should be spot on

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