Dear ErniemYou look these up in TABLE 17-6: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Timer0 256Two symbols Microchip uses you should know are Fosc and Tcy.
Fosc is the clock frequency your crystal runs at.
Tcy is the time to run a single instruction.
And for PICs:
Tcy = 4/Fosc or Tcy = Fosc/4
What is your clock frequency?
4MHz
What prescaler value are you using?
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