I'm fairly new at this, and I would like to know what DAQ cards are best recommended for controlling DC motors using a Digital I/O. I just need to generate a Square wave at 50 Hz and vary the duty cycle with a high degree of stability for 4 seperate motors at the same time (4 seperate signals). Currently, A USB device would be best due to space restrictions on the PC but if required, I have an open PCI express x16 slot on my PC. Also, price is a bit of a concern so the cheapest solution is the best in this case.
Although some customers have gotten away with using DAQ cards we strongly suggest using a Motion Controller cards. Unfortunately all of our motion controller cards are either in PCI or PXI form factor. For this reason I would suggest the NI 7334 Montion Controller card if you have a DC stepper motor. However if you are going to be using a DC Servo motor you will need to move up to the NI 7344. Both product pages are found below. Please let us know if you have any questions regarding these cards and we can help you further.