Re: [CAD_CAM_EDM_DRO] Re: sherline motor/speed control wiring IT WORKS!

----- Original Message -----
From: tauseef <alieron@...>

> One thing I have noticed is on boot up, no matter
> what the I/O says on CNCPro the motor is on. I think this might be a
> cncpro problem but am unsure. I have to cycle the I/O to turn it off.
> I have made a quick start up and shut down procedure that I follow to
> reduce any risks to my computer, stepper board and mill.

Tauseef;
I just went to the shop and looked at the I/O on my machine. IO3 comes on
momentarily during boot-up. IO4 then comes on and stays on until I load
CNCpro. All IO lines are set to enable low.

I've drawn a circuit that ties the e-stop to the enable pin of two 74ACT245
tranceivers through which all data and IO lines must pass on the breakout
board. Additionally, the e-stop circuit is tied to an enable button so the
machine comes up with all lines disabled.

The problem I have not worked out is what happens when you exit CNCpro to
edit a program. The lines stay enabled and are thus at the mercy of
whatever the computer decides to do with the parallel port. On my shop
machine the bits stay low so it has not been a problem. However,
Ctrl-Alt-Del (and some software?) may reset the port on some machines while
leaving the tranceivers on the breakout board enabled. Bummer!

I'm looking for a method of resetting the breakout board that will occur
automatically anytime the operator exits CNCpro.

Doug