I am using an ADuC845 (p/n ADUC845BCP62-3) and I am powering it from 3.0VDC. On page 56 of the user manual describing the PWMCON register it mentions that PWC1 and PWC0 (bits 0,1) can be set to choose the Fvco 12.58MHz PWM clock source selection. However, on page 60 it is stated that a 12.582912MHz core clock frequency is NOT allowed on the 3V part.
For my application I have set the PWM to be in mode #1 and the clock source to be 12.58MHz. The PWM appears to be working perfectly fine and the desired output frequency (1kHz) from the PWM is correct based on the clock source of 12.58MHz.
So I am a bit confused if the 12.58Mhz PWM clock source is valid or not for a 3V part?