Is there a way to change operation of ENA0 through ENA4 on a MESA 7i77D

The original control allowed disabling either or both of the X and Y axis drives for manual use with hand-wheels. The mill also has a standard Bridgeport style manual quill and the whole head assembly is mounted on linear slides for an additional 5" of controlled Z travel.

It's actually fairly useful. For example, disabling X to use it manually but keeping Y enabled to hold position.

I would like to incorporate this function with LinuxCNC and the 7i77D card. From what I've read, the floating enable switches (ENA0 to ENA4) are switched in common. Is there any way to separate them or would you recommend I used some of the unused outputs?

The drives are Yaskawa units and are enabled by a low signal. I did get the 7i77D version with sinking outputs.

Thanks,
Jim

The enable just turns on the enable pins and the analog outs. I just leave those enabled and use an IO pin to enable / disable each drive.