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Do I Have to Change Internal Interrupt Setups when I Change Clock Speed? The reason I ask is because I am trying to modify this code:
https://github.com/DccPlusPlus/BaseStation/blob/master/DCCpp_Uno/DCCpp_Uno.ino (Beginning at Line 289)
so that if will work on an ATmega328P-derivative board running at 3.3V and 8 MHz. I need the waveforms to be generated at the same speed, so is there anything I have to change? The original code is written for a 16 MHz uno or mega.
The equation for timer period is given by the following formula, where N is the value of the prescaler, TOP is the value given by either MAX (i.e. 0xFF, 0xFFFF) or the value in register OCRnx, and f is the frequency of the I/O clock.
If you're using phase-correct or phase- and frequency-correct mode, the factor (TOP+1) in the formula above should be replaced by 2 × TOP.
TOP. It's either 2 × TOP (in the phase-correct and phase-and-frequency-correct PWM modes) or TOP + 1 (in any other mode).
– Edgar Bonet
Nov 2 '17 at 15:00
