Local merge #1
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Checked the calculations by hand Use Datasheet 7.3.5 Equation 1 for frequency from prescale https://cdn-shop.adafruit.com/datasheets/PCA9685.pdf Frequency = (ClockFrequency/(PreScale+1))*(1/BitRate) and from the rest of the calculation us per period = PulseLength/Frequency us per bit = us per period/BitRate we can combine to get us per bit = (PulseLength/((ClockFrequency/(PreScale+1))*(1/BitRate)))*(1/BitRate) This can be simplified to (PulseLength (PreScale + 1))/ClockFrequency this formula was implemented in proposed code checked by setting chip frequency to 60Hz read prescale = 105 us per bit = 4.069 with 25Mhz (a PWM frequency of about 57.3hz) Choosing the FREQUENCY_CALIBRATED constant listed at 104.3% higher or 26.075MHz we get us per bit = 4.1035 or a PWM frequency of about 60.056Hz much closer to the set 60Hz Overall this change makes less calculation steps, and uses fewer variables. The change should be faster and more accurate to the intended results.
debug statements should be Wrapped in `#ifdef ENABLE_DEBUG_OUTPUT`
Prescale values are integers 3 to 255 with a maximum of 255+1 for the calculations.
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