View Full Version : Mach3 PC problems, help please....

29-01-2014, 03:27 PM
Hi all, I'm nearly ready to test my table now so i thought i'd get the board hooked up to mach3 and get the e-stop, limit and spindle/torch signals working and debugged.

The inputs are fine and perform as needed but i have no output to trigger the relay on the breakout board.

If i reboot the PC, the relay energises and stays on so I'm guessing the LPT port, cable and board/relay are all good.

As soon as i load mach3, the relay drops out and i cannot get it to re-energise again.

The leaflet says its on pin 9 and i have mach3 set for Output1 on pin 9 and spindle fwd/rev to #9

Any ideas as I'm stuck right now and can't progress.


29-01-2014, 03:55 PM
Just tried a fresh install on another PC, different make but exactly the same behaviour.

29-01-2014, 05:38 PM
Do you have a link to the breakout board ? also what is the relay for on the board ?
As a complete stab have you tried inverting the pin in Mach3 port&pins settings ?
Also does the board have a charge pump ? have you set this up in Mach3 or is there a link on the board to force it on all the time ?

29-01-2014, 05:56 PM
Hi it's eBay item 121246794423

Tried active high or low, no change.

no idea about charge pump, not mentioned in manual, just says spindle relay is on pin9, I want to use this relay to turn my plasma torch on/off.

29-01-2014, 06:56 PM
I think we are going to need some more information,

Assuming you have had no life whatsoever yet from your bob or steppers

unplug the parallel from the bob, if you google the pin layout for a standard parallel port, put your voltmeter across any of the ground pins, ie pin24, and the other lead to pin9 (you may need to exercise some paper clips)

see if the pin goes high (ie 3.3v) and low 0v when you send the signal from mach

I bet your computer is not even sending the signal properly yet, and therefore your problem lies in the mach setup as opposed to the bob.

either way we need some more information on the question your asking...post some screen shots of the various pin layouts in mach

29-01-2014, 07:42 PM

if I reboot the PC, when it comes up, the relay will turn on so the lead, bob and relays re all working ok.

as soon as I load mach3 it turns off and I can do no more with it, I don't even have to press reset, it kills it as soon as mach loads up.

i can't post pics as it's at work, but I have followed the setup leaflet from the bob supplier, relay is on pin 9 so they say.

29-01-2014, 09:36 PM
Have set the enables to pin 1 in the outputs.?

29-01-2014, 09:58 PM
Have set the enables to pin 1 in the outputs.?

Yes that has been done..

29-01-2014, 10:04 PM
Well the relay is designed to be turned on and off otherwise how would you turn the torch on and off. So with that in mind how are you trying to turn the relay on once Mach3 has loaded ?

30-01-2014, 06:27 AM
I have set output 1 to pin 9
spindle fwd/rev to output 1
issue m3/m5 or toggle the torch on/ off in mach.

30-01-2014, 08:19 AM

There was a little post i found on a google search.

There is a tick box - "Max CL Mode Enabled", this was checked, unchecking solved the issue :)

Happy days, thanks for the help.

30-01-2014, 09:08 AM
Good to hear you've got it working.

- Nick

30-01-2014, 09:22 AM
Check the LPT port in the computer Bios. Make sure it is enabled and set to bi-directional if that setting is available, else use ECP or EPP.

30-01-2014, 06:05 PM
Yes, the port is set as Ecp/Epp in bios.

all working now.