I am working at tuning some older digital (step/dir command) servos, that don't have any auto tuning capabilities. In order to avoid needing to use an oscillo scope I would like to be able to connect a square wave siggen signal to the velocity command input of an unused stepgen on a 7i76eu (I also have a 5i85 for encoder feedback.) I loaded the siggen, and made the hal connections, set all the parameters and enabled everything from halshow. I can see the input for the stepgen's velocity-cmd changing, but I don't think any steps are being generated (no changes of any of the stepgen's count or feedback pins.
Where am I going wrong? Is this another situation where changes to parameter pins are only effective in a hal file at startup?
I was hoping to just create a little hal file that I can load manually after Linuxcnc was running to set tuning parameters then plug one of the drives step/dir plugs into the testing plug to run the tuning (moving them back to their regular position when running.)