I need to generate one sine wave of 40 hz by timer A using an 20 Khz carrier frequency, if the lenght of timer A is 8 bits , i need one clock frequency of 5.12 Mhz ( Fclock = Fpwm*2^n), n=8, Fpwm=20000 hz.
If i use one sine table of 120 points the least frequency that i can see is 160 Hz, ( Fpwm/ 120), my question is, how can i get a 40 hz sine wave without vary the carrier frequency and the point of the sine table?
Thanks
Gastón