Disable cycle start / run button until conditions are met?

Hi all, I've searched for a while but can't find any info on how to do this, if there's a resource I missed please link me.

On my machine I have a few sensors for whether the operator has folded some fixtures away and I'd like to allow the machine to be on/jogging enabled etc but prevent starting a job if the sensors report that the fixtures are still out. How would I do this?

Basically I'd like to disable the start button until sensors A, B, and C report ok.

 

You can either physically add your sensors to your estop chain or you can build your estop chain in software with the estop-latch component. 

There is an example in the forum here under hal examples of using estop-latch but it only uses 1 estop but chaining them together is the way to solve this. 

Sorry, I should've been clearer; I don't want to estop the machine, i want the user to be able to jog the machine around and do all the normal manual things, I only want to disable starting an NC file.

It's more than just fixtures (it's about 7 sensors), it's also stuff like whether the door is shut - the user may need to move the machine with the door open, but shouldn't be able to start a job with the door open.

How would I do that?

Hmm I only could imagine to play with the homed state. So unhome the machine if one of the sensors A,B or C is not ok, otherwise home the machine. Not ideal but I have no better idea.
 

I think there are two options.
Hardware solution:
Use a separate push button for cycle start and connect all your sensors in line with it.

Software solution:
Write a custom comp like this not4 example and connect with halui.program.stop. If one of your sensor goes, off stop the program. To install this comp save file not4.comp in your folder and runand for the docs
​​​​​​​now you can see in
​​​​​​​the man page for how to use it or take the not4.hal file example.

Aciera wrote:

Maybe you could link your fixture sensors to the estop chain in hal to have them trigger an estop UNLESS mode-is.manual is true.

That's what Rod suggested and he doesn't want.

@Chris
I also thought about to immediately stop the program when one of the sensors is not ok.
But the start button would be clickable in this case.


Instead of compiling not4, this could be also done with lut5 linuxcnc.org/docs/2.9/html/man/man9/lut5.9.html

I look at lut5 several times but get a headache with this feature. too much for a mechanic's mind.

This problem is more tricky than expected.
If you are using logic with personality=0x1207  (7 input for sensor, 'or' and 'nor' output)

net the sensors to logic.0.in-0n

net the output as

It will inhibit spindle and feed, if a program is started, nothing happens. The dangerous about that, when all the sensors are released, the machine starts running, But it doesn't, because the 'nor' output is linked to 'halui.program.stop'  and will stop any started - and movement inhibited program.