PWM output from k8055

Hi,

I am a novice and am trying to run stepper motors using k8055. I wrote a looping program in c language and connected to one of the digital outputs, but the speed i get is too low. I thought i would be getting speed equivalent to the clock speed of the PC itself.

Then I thought to connect the motor driver to the PWM output. Again its revs at very high speed which is ok but now i am not able to control the speed. The stepper motor keeps on running at same speed even when the program is terminated!. my question is

what is the maximum and minimum step rate i can get from the board?
what is the step pulse width?
How to control them?
Is this the right board for the purpose?

My aim is to connect infrared sensors with the analog input and control the stepper motors.

The PWM output frequency is fixed and you can’t control the stepper motor speed by changing the pulse width.

The state of the digital outputs can be changed every 20ms. So the maximum step rate is 25Hz. If your C code is properly controlling the card you should get that frequency out from the digital output.

So… does that mean you can or cannot control a stepper motor with the k8055? If it is possible then how?

Hi,
As i wrote before i could not run stepper motor at descent speed. 25hz being very low. so finally i decided to directly use parallel port output to control steppers and control sensors with k8055. havent got time to get it working tho!!

[quote=“londonrulz”]Hi,
As i wrote before i could not run stepper motor at descent speed. 25hz being very low. so finally i decided to directly use parallel port output to control steppers and control sensors with k8055. havent got time to get it working tho!![/quote]

20 ms is not 25 Hz, is 50 Hz. That means 50 pulses per second. Still, at 1.8 deg/step, would be 90 deg/sec, means would take 4 seconds per revolution; that’s normal speed for a stepper. If you want faster, get a different stepper, a 36deg/step, that I’m not sure will even follow the 20ms timing, meaning 5 turns per second, 300rpm.