hi i need help to create a vb code to control dc motor speed
i already created the code to supply pwm signal to the motor driver but users need to give an input in duty cycle in vb's GUI

but actually i am required to create a code so that users can give an input in rpm

hope someone can help me

the pwm signal is sent to the motor driver via 1 port in parallel port

 

Sounds slick. How do you do the low level control out of the printer port? I thought VB didn't let you get to hardware. How is the port configured - SPP or EPP?

We can't help with the change from duty cycle, as we have no idea about the motor. I think if you measure the motor speed with each increment of duty cycle, you can make up a table to look up duty cycle from a desired RPM input.

That should not take you 10 minutes, once you have the motor speed measured.