Thanks Bruce - I now have some level of success !??!

I was stuck for a while with only getting a Vref output from the 4812 - no matter what 10 bit information I loaded it was the same. I just had to change the mode on the SHIFTOUT command to a 1 or MSB first and it fell in line.

For this example, you are predefining the 10 bits for conversion in A and B. How would I load up 'A' with the same first 4 bits but then the next 12 (10) bits varying, based on my PID loop output?

Thanks again ...