integrating a go/pause switch into LinuxCNC (not an estop)

Hi Guys, I've been learning a lot, but I need some help. I'm building an semi automation machine that has a switch to let the machine know if the product is loaded. Here's how it works--an operator pushes a loaded pallet into a hard stop and switch, and I want that to trigger the program start and then pause if the pallet is pulled out.

I've been able to configure the switch to be an e-stop, but that's not what I'm looking for, because the operator would have to reset the e-stop, turn on power, and run the program every cycle.

Here's what I want it to do:

Run the program if the switch is opened. The switch is on pin 15 (and 5V) right now, configured as digital in 1.
Pause the program if the switch is closed.
Resume when the switch is opened again.

Any idea how to configure this?

---OR---

I could just use the switch to pause and resume, and rely on the operator to press a pvVCP start button.

Which ever is easier. Any help would be greatly appreciated. I started to try to do this with Classicladder, but I got lost.

Thanks! Now to see if I can actually get it working! I'm really new to this hal editing stuff.

Ok, I added the code with no changes except changing pin-01 to pin-15.

It couldn't load and2, but I think it was because "count-2" should be "count=2".

After changing that to =, I'm getting the following error:

Pin 'and2.0.in0' was already linked to signal 'button_closed'

it was just another little typo change the second and2.0.in0 in your file to and2.1.in0.

I'm 95% there! It's pausing when I want it to, and resuming, but it is getting an error when loading another pallet and starting the program again:

can't do that (EMC_TASK_PLAN_RUN:507 in manual mode

Is there an auto mode that I should be switching into?

Thanks so much for your help! I'm definitely going to be posting the final hal file when it gets resolved!

I'm thinking I need this in there somewhere, but I'm not sure how to use it:

halui.mode.auto

-Edited due to bad info on my part-

I added halui.mode.auto but now it automatically goes into the next cycle without me removing pallet. I'm aslo getting errors. I'm guessing I need some logic about when to go into auto mode?

Here's my HAL file:

loadrt and2 count=2
addf and2.0 servo-thread
addf and2.1 servo-thread

net button_closed parport.0.pin-15-in => and2.0.in0
net button_open parport.0.pin-15-in-not => and2.1.in0

net machine-idle halui.program.is-idle => and2.0.in1
net machine-running halui.program.is-running => and2.1.in1

net start-cycle halui.mode.auto and2.0.out => halui.program.run
net pause-motion and2.1.out => motion.feed-inhibit