[R.thayer]

I have a small table top lathe that has a minarik spindle drive. This drive uses a 0-10v analog signal to control the speed of the motor. I am using linuxcnc to control the motion of the machine now I would like to be able to control the speed of the spindle and send the spindle encoder signals back to the control. I was wonder if there was something I could build to convert the pwm signal coming from the parallel port pin to a analog signal that would control my spindle ? I was wondering if a low by-pass filter and op amp would do the trick. Please pass along any information that you can thing of that will help me make this work. Thank you and hope to hear from you.

[doorknob]

Here is a commercial board that does exactly that (maybe you can get some ideas from it):

http://cnc4pc.com/Tech_Docs/C41R1_1_User_Manual.pdf

CNC4PC

[chester88]

I have used an op amp to create a voltage to run a servo for testing, using the parallel port.
It would surely work for spindle control. The resolution of the voltage is not that good with the parallel port but it's pretty cheap...One thing I remember when I did it was I set the resister values for a 5 volt parallel port when it was actually 3.3 so remember to check the ports output levels.