Mesa 5i25 & 7i76 to GE Af-300 VFD?

panchula wrote:

I ended up using a DPDT for the enable so I could incorporate the enable to control other functions dependent on the spindle running -- lube pump, air motor speed adjust of the varispeed head, etc.

That sort of interlocking is far easier to implement and adjust in the HAL layer than with actual wires and relays. (though it may not seem that way if you know relays but don't know HAL)

panchula wrote:

OK Andy, now you've got me thinking... is there a way to integrate the VFD and varispeed head to get a continuous (non-back geared) low to high range utilizing both?

Almost certainly, the hardest part is likely to be deciding how you want it to work.

I would guess that the ideal is to run the motor at nominal speed where possible with speed control on the varispeed, and to only go to higher or lower frequency when out of range? Or would you prefer the opposite?

I'm still having trouble with the spindle not responding to F9.

Under what circumstances? You probably need to be in manual mode, and might need to be homed for it to work.
Is it just F9 that is a problem, or can you not click in the GUI either?

One other item is I can't get the spindle encoder to be recognized. It's a Renco 100 ppr differential. I'm seeing voltages at the pins (Fluke 77) when the spindle is running.

As far as I can see the HAL wiring is correct. You should be able to Halscope the A and B inputs (but only at low encoder speed) and see them change state. The dmesg output will tell you which GPIO pins of the 5i25 the encoder is on.