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AT91 variant HAL timers and AT91 ADC


Hi!

I'm writing an AT91 ADC driver, and was looking for a timer to use for
triggering the ADC sampling.
There is no problem when the PIT is used for eCos clock, in this case
the delay_us() also uses the PIT. But when the TC is used as the eCos
clock, then TC0 is used for the clock and TC2 (TC1 in the case of
CYGHWR_HAL_ARM_AT91_JTST, because TC2 is used for the AD/DA) for the
delay_us(). The eCosPro documentation states that TC1 is used for the
profiler (it's more interesting with JTST), but it is not implemented
in the free CVS version.
The point is, that I'm not very happy with the current solution. Why
to use a separate timer with hardware compare, when delay_us is a
blocking function doing polling? I think it would be better to use the
same timer as for the eCos clock, as it is done in the PIT version. In
this case, TC1 can be reserved for the profiler and TC2 can be used
for the ADC (as in the JTST).
I can rewrite it, but first I would like to hear your opinions.

Gabor

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