How to configure 7I92+DMM BOB

You may need to lower the PWM frequency.

No or low output until you get a significant duty cycle
suggests that the PWM rate is too high for the isolation
devices (they simply don't "see" narrow PWM pulses)

And yes, you can add software MPG encoders on the parallel port
(man encoder)

Another option if you are not using the second 7I92 port,
firmware the included some MPG encoders could be installed.

PCW wrote:

You may need to lower the PWM frequency.

No or low output until you get a significant duty cycle
suggests that the PWM rate is too high for the isolation
devices (they simply don't "see" narrow PWM pulses)

And yes, you can add software MPG encoders on the parallel port
(man encoder)

Another option if you are not using the second 7I92 port,
firmware the included some MPG encoders could be installed.

The PWM frequency did the trick as you suggested.
I changed it from 20000 to 2000 and now I get the full range of speed, although I noticed some slight hunting of the frequency at the VFD. I'll play with the PWM frequency a bit more later.
I suspect I'll need to have very steady speed to screwcut with only 1 pulse per rev.
I will probably end up attaching an encoder to the spindle if it doesn't work.

For anyone else looking for the PWM frequency in Hal it's near the first few lines at the top - not in the Spindle section.
Thanks for your help.

I'm using the parallel port 0x378 for the spindle input encoder and MPGs ( MPGs not done yet )
I've added the encoder for the spindle ( 1 pulse per revolution )but I can't get the spindle at speed function to work with the actual speed.
The light comes on for spindle at speed as soon as I turn on the spindle whether it's actually rotating or not.

I don't know how to get the display to show actual spindle RPM instead of ( or as well as ) commanded RPM.

I can't get the channel A and index Z to use the same pin ie. parport.0.pin-12-in
I tried :
net spindle-index encoder.2.phase-Z spindle-phase-a encoder.2.phase-A <= parport.0.pin-12-in
but I get an error :
./Lathe_2.hal:252: Pin 'spindle-phase-a' does not exist.

If I use separate inputs I don't get the error but I would have to wire the 2 inputs together on the breakout board.

If I replace
net spindle-at-speed => spindle.0.at-speed
with
net spindle-at-speed => near.0.out
I get the error message:
./Lathe_2.hal:218: Pin 'near.0.out' does not exist
but I have
net spindle-at-speed spindle.0.at-speed <= near.0.out
near the bottom of the spindle section

I've attached my Hal file and have a few things I've tried commented out.

I've been working on this most nights after work
Any help is greatly appreciated. Thanks.