TL;DR Electronics - PIC TMR0 Calculator

Use the calculator below to determine the register values needed for a timer 0 overflow period of frequency. This calculator is typically used for enhanced mid-range PIC microcontroller devices.

Oscillator Frequency [f_OSC] (Hz): Overflow Frequency [f_out] (Hz): Or Overflow Period [t_OUT] (S) :

T0PS	TMRx	Actual Period	Actual Frequency	Error (%)
2	6	0.004	250.000	0.00
4	131	0.004	250.000	0.00
8	194	0.004	252.016	0.81
16	225	0.004	252.016	0.81
32	240	0.004	244.141	-2.34
64	248	0.004	244.141	-2.34
128	252	0.004	244.141	-2.34
256	254	0.004	244.141	-2.34

Disclaimer

This calculator is intended for reference only. While efforts have been made to ensure the accuracy of calculations, no warranty is provided. Users must independently verify results before applying them in design, testing, or production. This tool is not intended for safety-critical or certified applications. Use at your own risk.