Stepper Control with labjack

[Jonnyenglish]

Hi everybody,

Im doing a project at uni that requires me to control a small stepper with labview. The program I developed can generate the correct binary sequence (using a 4 element array) but the problem im having is obtaining a high enough frequency to drive the motor at sufficient speed. Two pieces of hardware that ive tried to use are Labjack and NI ELVIS(to output the signals). I now Have access to NI DAQPad-6015.

[AnalogKid2DigitalMan]

What frequency range do you need?

Using discrete digital outputs toggling on/off, you will be limited by the iteration speed of your software loop. This is probably limited to 100's of Herzt, most likely less than 1KHz. Post your code, maybe we can help. Please note that software timing can be indeterminate due to Windoze overhead- the speed of your motor may not be constant. Also note that your stepper may stall out if you command it to accelerate too fast.

The other option is that the DAQPad-6015 has 2 counter/timers that you can use to generate a wide range of frequencies and dynamically change and ramp up and down in frequency. But you would also need additional simple hardware (state decoder) to generate the 4 discrete phase signals that go to the motor drive electronics.

[Steve]

Serial port controllers with drivers are availabel for $100 or less
with settable acceleration and other parameters.

http://www.stepperboard.com/
http://www.weedtech.com/