At 04:35 PM 11/3/02 -0500, Larry Bradley wrote:
>I'm looking at using a voltage to frequency counter in an app, feeding the
>pulse train into an 16F877 to measure the frequency.  I haven't played with
>the newer PICS with their fancy additional hardware.
>
>What is the maximum frequency I'm likely to be able to measure with a 20
>MHz '877? Will it handle 100 kHz?

Easily.  You should be able to do somewhere near 40 MHz, if I remember
correctly.

There is a frequency counter design that uses TMR0 in a 16c54 to measure up
to 50 MHz.  Surprisingly, the newer 16f87x family is not as capable.  Also
note that the clock frequency of the PIC does not limit the maximum
frequency that you can measure - that 50 MHz freq counter design I
mentioned earlier runs at 4 MHz.

dwayne

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Dwayne Reid   <dwayner@planet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
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