Controling the state of a pin?

I want to use custom M codes to control the state of some pins. I also need to be able to indicate what the state of that pin is in a pyvcp pannel. My problem is that if I connect the pins to signals to twiddle the led in the pyvcp, then I can not control the state of the pin with setp in the custom M code. I am sure there has to be a way arround this, I just don't know what it is.

I have the pin (lut5.0.in-2) that I want to control with setp, in custom M codesand
I also want to twidle it with pyvcp buttons, no problem just use halui commands to the custom M codes.

My problem, is I want to have some indication on the pyvcp of what the state of the lut5.0.in-2 1
pin is. How do I do that without breaking the M codes?

I haven't actually tried anything yet. I am still working at typing up all the configuration files.
Maybe I can just add another setp line in the M code to directly effect the pyvcp pin for the LED.

I completely missed that there was a "sets" command in hal. That makes my life much simpler.

I don't think "sets" is mentioned in most of the manuals. (it is in linuxcnc.org/docs/html/man/man1/halcmd.1.html)

Now that I have it working I can better explain what I was trying to do.

We have some routers with two spindles on W and Z axis. Some times both are used together to mill 2 things at a time. Other times they are used separately to do to separate tasks on a single piece. Such as one milling a key hole slot with a t-slot bit, and the other using an end mill to cut out the piece.

So I created 4 M codes M113 and M123 to enable Z and W and M115 and M125 to disable each. So to run both spindles I would first command M113 and M123 then S18000 M3. If I need to run just the W spindle I would command M115 and M123 before the M3.

I used the lut5 to control the inputs for the spindle at speed signals. So that if one of the drives is disabled then LinuxCNC only waits for the signal from the enabled drive, and if both are enabled then the signal must come from both drives.

Then I used two and2 gates to connect each spindle enable signal and the spindle on so that only the drive(s) that are enabled start when the M3 is commanded.

Finally, I set up some pyvcp LEDs to indicate what spindle(s) are enabled so you know what it going to start when you press the start button, and a couple of buttons to manually set them.

I had been mulling this over in my head on and off for the last 6 months. It feels really good to finally have it set up and work as planned. If anyone wants me to share the config, I'll zip it up and post it. It is kind of involved with lots of little osubs and the M1xx codes to work with the pvcp. (I think there are 44 halui commands in there)

hell your brain must be fried by now Todd .. glad you figured it out
post your configs etc , this sounds interesting to try out !

You asked for it so here it is