SynthModules

As I use my PSIM for CV functions, the output never seems to be 'in
tune' with what I expect.  If I use the basicqu2.bas program as an
example to sample and quantize my keyboard CV, there is a
significant difference between the output and the keyboard CV.

I thought I would try and do the calculations in semitones.  The
input is 1023 steps over 10 volts.  Every 8.5 steps is a semitone (83
mV).  If I could divide the input by 8.5 then I would have the
semitone value. Since I can't divide by 8.5, I can multiply by 2 and
divide by 17.

Since the output is 4095 steps over 10.666 volts, every 32 steps is a
semitone. To convert the input from a semitone to the correct output
voltage, I would multiply by 32.  Thus if I take the input, multiply
by 64 and divide by 17 I convert it to the correct output and
quantize to the semitone.

In basicqu2, replacing the RAWDAC1=((ADC1V/16)*32)+49152 calculation
with RAWDAC1=((ADC1V*64)/17)+49152 yields an output that tracks the
keyboard CV quite well.

Does this math make sense?  I haven't seen any code use anything
similar to this.  I've been having issues with a program I'm writing
that samples and delays my keyboard output and this seems to correct
the issue.

Dave