I had asked a question about this a while ago and got no answers (as far as i remember). This involves Microtech I controllers through an OPM -> JCI MIG -> Jace
The warm/cool adjust point read fine on the NCM showing (3,2,1,-1,-2,-3) but randomly we would see numbers like 65533 shown on the Jace. I finally got around to looking into it again and finally noticed it was only when a negative number was shown and sure enough 65533,34,35 are a 16bit equivalent to those negative numbers. Why is it doing this? I dunno but it was easy enough to compensate for.
Our fix was to delete the numeric points and make new enumerated points to make it look normal to the customer. Now i don't have to say "No Mr. Customer, it is not trying to make your room start on fire."