100MHz frequency counter with PIC16F628A – LCD Display

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Joined Jan 27, 2015
What's this look like for a freq-counter ? Looks nice and small, as much as I might want a lab full of "_________" from all branches of science, I don't have the space anyways.
The max frequency of Timer0 is 1/4 of the CPU clock which is 1MHz, but there is internal prescaler and it can be set from 1 to 256. In theory this can allow the input signal to be up to 256MHz. On the other hand, in the datasheet of 16F628A there is a requirement for the input pulse at RA4 to be with minimum width of 10ns which is 100MHz frequency. So the maximum frequency can be between 100Mhz and 256MHz. I checked with two different PIC16F628A and they easily go over 200Mhz barrier.
I can get 4x PIC16F628A's for $15, IDK about other silicon and LCD
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