Mary, I was thinking the same thing, but .005 is a large difference. Here is what I come up with:
0x3F66 6667 (Highest value that will display 0.9)
0x3FCC 28F9 (Highest value that will display 1.595)
Result of adding these is still 2.495 displayed (0x401FAE16)
@optonovice Can you post the code where you are adding those two numbers? Is it possible they are getting written to in more than one place?
Also, FWIW, I don't think you are going to get very precise positioning using timers if 5ms is critical. Do you have any other forms of feedback, like an encoder? Can you describe what you are trying to accomplish?
Idea: If you need to know the exact rotations of your stepper, you could feedback the output of the SNAP-SCM-ST2 into an SNAP-IDC-FAST module if you are using an R1 or EB1 brain (25kHz max) to get an accurate pulse count. You will probably need to decelerate the stepper when you approach your target to precisely stop it.