CV 9

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CV 9
Total PWM Period
Range of Values0-255
Accepted ValuesN/A
Default Value0

NMRA CV 9 - Total PWM Period

The value of CV#9 sets the nominal PWM period at the decoder output and therefore the frequency is proportional to the reciprocal of the value.
The recommend formula for PWM period should be:

PWM period (uS) = (131 + MANTISSA x 4)x 2 EXP

Where MANTISSA is in bits 0-4 bits of CV#9 (low order) and EXP is bits 5-7 for CV#9. If the value programmed into CV-9 falls outside a decoder's capability, it is suggested (but not required) that the decoder "adjust" the value to the appropriate highest or lowest setting supported by the decoder