controlling axis 'machine power' from HAL?

Until today I used to have a very simple Estop solution: it just removes the mains power to the spindle and stepperdrives. Of course this works, but LinuxCNC doesn't know that I hit the button and keeps on executing the G-code program. Not an ideal situation when there are many short moves.

Today I modified that a little; a piece of extra electronics determines if mains voltage is present and sends a signal to the PC to control LinuxCNC's estop.
(net estop-ext <= parport.0.pin-13-in-not, net estop-ext => iocontrol.0.emc-enable-in).

Now, since I also use the big red mushroomed button to turn on/off the machine and related circuitry, the 'machine power' button in AXIS makes no sense anymore. It is annoying that I have to start axis/Linuxcnc, do whatever preparations I have to do, release the big mushroomed button, and then click the machine power button (or press F2).

Is there a way to either:
- start up AXIS with 'machine power' enabled.
- make 'machine power' the inverse of estop? (might be a little tricky when a limit switch is hit though...)

Hi

I don't think your plans are the way to go.

The E in EStop stands for Emergency, if you hit it, it should cut power to everything mechanical.
It should also stop the controller and be linked to iocontrol.0.emc-enable-in

The machine on/off is different, this should stop the enable feed to the drivers via motion.enable.
It also disables the the GUI, but when you click it back on, everything is exactly as it was.

Setting iocontrol.0.emc-enable-in FALSE will also set motion.enable. FALSE, but resetting EStop does not turn the machine back on.

That is exactly how it is supposed to be, if you have needed to hit EStop, the last thing you want is for everything to be powered up and enabled again as soon as
you reset the red mushroom button.

regards

ArcEye wrote:

Hi
The E in EStop stands for Emergency, if you hit it, it should cut power to everything mechanical.

It does just that; it cuts the (mains) power to stepper drives/spindle/mist coolant pump/lights/etc.

It should also stop the controller and be linked to iocontrol.0.emc-enable-in

This is the case also. Once the 230V mains disappears from the milling electrics iocontrol.0.emc-enable-in goes inactive (and the estop icon in axis reflects this)

The machine on/off is different, this should stop the enable feed to the drivers via motion.enable.[
It also disables the the GUI, but when you click it back on, everything is exactly as it was.
Setting iocontrol.0.emc-enable-in FALSE will also set motion.enable. FALSE, but resetting EStop does not turn the machine back on.

So machine power acts more like a 'pause' button. I don't see the added value of that construction. Or the added value of concept 'machine power'.
Estop = power down everything except the computer = the safest and surest way to stop things.

That is exactly how it is supposed to be, if you have needed to hit EStop, the last thing you want is for everything to be powered up and enabled again as soon as
you reset the red mushroom button.

No, you don't. But sending the estop signal to the computer also causes LinuxCNC to stop it's operations.
With the machine power button disabled it is impossible to do anything in software since the GUI is disabled also, So I still don't see added value. It might as well be the inverse of Estop and nothing changes in functionality.

BigJohnT wrote:

I wonder why your using the Emergency Stop for machine power on/off?

Uh, since it does just that, turn on/off the machine power (except computer and compressed air), so it acts like a mains switch.
And since it takes extra effort to enable the button (twist and pull), it is quite a safe mains switch too.