Control 2-stepper motors with PCI-7342

[rkorpu]

Hello,

I have 2 compumotor zeta stepper motors driving a X-Y carriage. They have 200 steps/rev and 10 micrsteps/rev. The carriage has a 1mm lead screw. The motors are connected to a NI MID-7602 and a NI PCI-7342 stepper motion controller. I have written a code to control these stepper motors. The problem is the motors dont move the required no of revolutions.

What I want to do is to reach a desired position (say 40 along x) and then move back according to the no of intervals( say 8). So the motor has to start at 40 stop at 35 for 1000 ms and then reach 30 and stop for 1000ms and so on to the initial position. It has to go back the same way to 40 from 0.

The carriage reaches different positions for the same values during different runs. How should I proceed from here?

I am postiong this question out of dispair. Please HELP! 

[Hockeyjim07]

just to clarify, you have the profile set for 2000 steps / rev correct? What do you mean by it reaches different values during different runs. As in you enter 10 steps and sometimes it moves 10 and others it moves 15?

[rkorpu]

Hello,

That is exactly what happens. I want to move 40mm in 40 steps. So every 2000 steps move the carriage by 1mm. When I enter 80000 steps, its sometimes moves to 25mm and stops, sometimes to 60mm or 10mm or 15mm and stops. The motor makes electronic noises but doesnt move and the program is still running. It shows no errors as well. (Intially I though it was a following error but I set the following error to "0"). 

In an other instance, when I give a value of 0 in Y axis, the Y motor activates for some reason till it hits the limit switch.