Generating variable frequency square waves
Dan Michaels email (remove spam text)
This is not quite what you are after, but ----
Since you are using a '74, if you want "rock-steady" pulsetrain
output, not dependent upon any software, you might also look at
using the PWM modules. You can only get one frequency this way,
but you can get 2 different pulsewidths or duty cycles.
With 10Mhz xtal, you can get 2.500 Mhz down to 600 hz - it obviously
scales by xtal value. Frequency selections are a little "grainy"
on the high end - 2.5, 1.25, .8333, .625, .500, .4166, .357, .275,
.250, etc. However, rock-steady pulse generation.
This works because the PWM registers on the PICs are totally
programmable for any pulse width and pulse periods. For more info,
I have an appnote on this:
"AN-ECD06 - Precision 50-nsec Pulse Generation Using a PIC16C63"
- Dan Michaels
tom sefranek wrote:
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