[gurvy]

What drives an Analog velocity signal in a servo amp?
Can this be done directly from the computer, Program an IC?
or otherwise?
How do I deal with the motor encoder outputs to drive an analog velocity signal from the computer?
Hope someone can help?
Thanks in Advance

[Al_The_Man]

To use a PC you generally need a motion card or other with analogue output. The loop is closed back to the motion card via the cards encoder input.
If you use a software based control like mach etc, the signal to the drives is step & direction through the parallel port, so if you have analogue drives you need a S/D to analogue conversion I believe if you search here for Pixie it will show up.
For an example of a closed Motion card look on the Galil Motion site.
Al.