Is there anyone out there who can offer some help to a total beginner in this field?
I have built an apparatus to move a digital camera to any position on a 1.5m x 1.0 m plane. The mechanics work beautifully. I am using an old laptop (Windows 98, which has DOS QBASIC built in) to control two stepper motors to provide x and y movement via the parallel port. A relatively simple BASIC program can calculate the various x and y coordinates from the optical parameters ( I understand optics better than cybernetics!) and send out the appropriate pulses. I have built a simple 3 channel CNC driver from a kit but this leads to frequent missed steps, even at slow pulse rates and under zero load, whether single or half stepping, and anything faster than about 20 pulses per second increases the frequency of missed steps or just causes the motors to chatter.
I guess I have two questions:
Can anyone recommend a simple 3 channel driver (ready assembled or in kit form) that I can use for this application?
Am I being unduly simplitic or is it ok to control motors from appropriate bit sequences generated from a BASIC program and sent via the parrallel port? Is there some essential fact I'm missing?
Many thanks to any kind soul who can advise.
Merv M
Tasmania, Australia