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Guest
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Timer0: is my thinking correct?? |
Posted: Tue Mar 27, 2007 1:37 pm |
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Hi All,
I am using a 12F629 device with the internal 4 MHz oscillator. With this configuration, I believe that each clock cycle is 1 us, and thus the Timer0 can potentially increment every 4 us (Fosc/4). Is that correct?
Then if I further prescale this value by 16, the actual timer increment period
is 64 uS (16 X 4 uS).
Am I thinking about this correctly, because I'm getting consistently strange results when I try to use Timer0 to measure the duration of a known pulse width.
[code}
setup_counters( RTCC_INTERNAL, RTCC_DIV_16 );
[/code]
Thanks,
Charles |
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PCM programmer
Joined: 06 Sep 2003 Posts: 21708
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Posted: Tue Mar 27, 2007 1:43 pm |
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Quote: |
I am using a 12F629 device with the internal 4 MHz oscillator. With this
configuration, I believe that each clock cycle is 1 us, and thus the
Timer0 can potentially increment every 4 us (Fosc/4). Is that correct? |
The oscillator freq is 4 MHz, so the oscillator period is 250 ns.
The instruction cycle clock is 1/4 of the oscillator freq. Therefore
it's 1 MHz, and the instruction cycle clock period is 1 us.
The timers run off the instruction cycle clock. |
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