Joe,
     Very true and I was going to add the ability to change the counting=20
time after I got the basic system up and working. In fact if we want to=20
we could do a very simple case of hold the count gate open for 1 second.=20
Display the value for 15 seconds. Reset the display with the 20-30ns=20
pulse. In fact I would use at least 30ns as 20ns is the minimum=20
specified time for the reset pulse. Open the counting gate again for 1=20
second and repeat forever. No ADC, pot or the code to read and process=20
the reading.
Thanks,
rich!

On 7/18/2014 5:10 AM, IVP wrote:
>>> Less than 1 percent would be worst case. If 1ppm could be
>>> achieved that would be great but I don't know if that is possible.
>>> I'm not going to use it for calibration work.
>> But what is your crystal accuracy?
> The meaningfulness of the result rather depends on what signal
> frequency is being measured. For example, if it's only a few kHz
> then the portion of a wave left off the count when the 1s is up
> could be more significant than the ppm error of the PIC crystal
>
> Joe
>
> Nice to see some PIC on the list

--=20
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