Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: Yianni - VJ - Glaux on April 27, 2010, 09:41:56 AM

Title: Problem homing when Autozero is disabled.
Post by: Yianni - VJ - Glaux on April 27, 2010, 09:41:56 AM

Hello People,

Just installed Mach3,
Hardware: STDR-4C - GeckoG540

When i disable the AutoZero function in homing each axis goes crazy, it goes to reach the limit switch and once it does then it moves in sync with another axis while it tries to home. Difficult to put in to words...

Any intake on what could be wrong?

Title: Re: Problem homing when Autozero is disabled.
Post by: Hood on April 27, 2010, 04:55:23 PM

Shouldnt be a problem disabling AutoZero but actually wondering why you would do that anyway?

If you want to attach your xml I will see if I can repeat your problem here.
Hood

Title: Re: Problem homing when Autozero is disabled.
Post by: Yianni - VJ - Glaux on April 27, 2010, 07:01:37 PM

Thanks for offering to have a shot at it. Here is my XML,
I want to disable Autozero to verify that i have no significant loss of steps after running a large G-code.
Is there any better way to do that?
Even if there is i wonder why this erroneous behavior.

Title: Re: Problem homing when Autozero is disabled.
Post by: Hood on April 27, 2010, 07:38:34 PM

Ah Ok just tried your xml and I see you are using the SmoothStepper. I will have to test this out tomorrow and see what happens. Having said that what you should really be doing is using the verify button, I have never tested it with the SmoothStepper but Verify is supposed to work in the latest plugin.
Hood

Title: Re: Problem homing when Autozero is disabled.
Post by: Jeff_Birt on April 28, 2010, 04:40:08 PM

Hi Hood :) I have confirmed that the problem occurs with the SmoothStepper and not the LPT driver. The situation is complicated as the 'Verify' button also does strange things. I've been talking to Greg about the problem, though we have not found the cause on Greg's suggestion I tried a G28.1 with each axis individually which will home that one axis properly no matter that the 'Auto Zero' mode.

So it looks like a work around at this time is to first keep 'Auto Zero' turned on, reference all, turn 'Auto Zero' off and then us the MDI input to run a G28.1 on each axis. (i.e. G28.1 Z0, wait until it is done then G28.1 Y0, etc). I'll try and remember to update this thread when a solution is found.

Title: Re: Problem homing when Autozero is disabled.
Post by: Hood on April 28, 2010, 06:23:03 PM

Thanks Jeff, been too busy at the workshop to test anything, you saved me the trouble :)

Hood

Title: Re: Problem homing when Autozero is disabled.
Post by: Yianni - VJ - Glaux on April 28, 2010, 06:57:17 PM

It seams Autozero and Verify are not the only issue here.

Trying to home the machine before you run a G-code works fine if autozero is checked.
Stopping a G-code and trying to home all hell brakes loose, same like disabling Autozero.

Can somebody duplicate this error too and suggest a solution ?

Thanks.

Title: Re: Problem homing when Autozero is disabled.
Post by: Jeff_Birt on April 28, 2010, 07:03:21 PM

Are you stopping mid program or at the end of a program? I've not had a problem homing at all with 'Auto Zero' turned on, just with it turned off.

Title: Re: Problem homing when Autozero is disabled.
Post by: Yianni - VJ - Glaux on April 28, 2010, 07:14:38 PM

I m stopping mid program,
I didn't try waiting for a code to finish, will do though.

Title: Re: Problem homing when Autozero is disabled.
Post by: Jeff_Birt on April 28, 2010, 07:38:25 PM

Hmmm...homing mid program while it is not a typical operation should not cause problems I think. Currently though, if you try to reference all axis with 'Auto Zero' off it will do silly things. See my post above about using the G28.1 command for the MDI line, generally I would suggest waiting until motion stops before commanding a new motion.