> I need to generate 46.25 us interrupt this is how I calculated
> Using 16 mhz crystal  256-185=71 if I put 71 in timer0
> I should get  185/4=46.25 us interrupt. 2 cycle latency for
> Timer0 and 5 cycle latency for interrupt service routine I get
> 71-2-5 should be 64 so if I put 64 in timer0 I should get close
> to 46us but it is not. By changing the number I got TMR0L=119

If I understand you correctly, you're using 2 + 7 extra cycles
outside of TMR0 so you'd add that to the 71 to make TMR0
run for a shorter time before it rolls over, ie TMR0 counts
(256 - (71+2+7)) * 0.25us = 44us.

Putting 64 in TMR0 would get you 192 * 0.25us = 48us. I can't
explain the 119. You aren't confusing it with 77h are you ?

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