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I am trying to connect pin 16 of my parport 0 to a SSR relay to turn on the driver board when I turn on the power putton so the driver board is not running all the time. I am not sure I can do it the way I am trying so I need help. This should be easy for you guys. What I have tried is
[ net machine.is-on => parport.0.pin-16-out ]
in the .hal file. Hal meter shows is false with power button on and off. Hal configuration shows , halui.machine.is-on, true and false when clicking the power button on and off. Thanks for any help. Carl

What you have done is created a signal named "machine.is-on" and connected it to your parallel port pin. That will not do any thing by it self.

Read about the net command here.

The simple way is to add the pin "halui.machine.is-on" to your net.

John

Sorry John but I don't understand your answer.
Reading the Basic HAL Tutorial gives me the empression that I can't assign a pin because I have a joypad using that signal.

"An OUT pin can be connected only if there are no other OUT or IO pins on the signal."

I have a button on the USB joypad used to turn the power button on.

Still lost , Carl

A "signal" can be used on more than one line and you can have as many readers as you want but only one speaker so to speak.

If you have two things toggling an input like coolant you need to look at this example. There are a few more examples like that in that section.

So you have your joypad button turning on the power using halui.machine.on? The pin halui.machine.is-on is a different pin... so no conflict there.

Attach your .hal file(s) so we can look at them.

John

Here is my .hal file. I only have the one entry that I tried last. This attachment is hidden for guests. Please log in or register to see it.

Hi

halui.machine.is-on is an exported PIN from the halui module

Your entryis treating it as a SIGNAL, which is why it doesn't work

As John said earlier the syntax needs to be

net SIGNAL PIN [PIN....]

so net powered-up halui.machine.is-on => parport.0.pin-16-out

will create a signal called powered-up which other pins can link to if required and links parport.0.pin-16-out to the boolean halui.machine.is-on value.

I think of signals as pieces of bare wire that physically wrap between pins and connect them.
Another pin cannot connect to the same pins but it can connect to the bare wire and share the same signal.

Hope this analogy helps, once you have it straight in your head the whole thing falls into place.

regards