Machsupport Forum

Mach Discussion => Mach4 General Discussion => Topic started by: royce on August 01, 2015, 12:24:45 AM

Title: Single Switch, Homing + Limits
Post by: royce on August 01, 2015, 12:24:45 AM
I've been scouring the forums for the past couple months now and have spent the last two months completely retrofitting new controls for a Bridgeport Boss 5 Series 1 CNC. I'm using a PMDX-126 BOB & ESS, along with the original steppers and Leadshine DM2282 drivers. The first thing I did before my controls were built was wiring the limit switches to NC. With these Bridgeports, as far as the X+Y axis go, its only one limit switch. I've assigned them in mach, and have the limits working properly. However i'm having troubles setting up the homing. I.E., in M4 X axis has --, ++ & Home as the same input. When I try to home my axis it will of course hit the limit switch. I am unable to limit override and jog off because Mach sees + & - hit (my theory). This freezes movement on X,Y & Z axis. I have to manually disable the + axis to jog off the switches, restarting Mach4 several times. Also it seems that if I close Mach when a limit switch has been hit, it won't show it under diagnostics on next start up. It will only show that the limit switch has been hit if I go into the Mach setup screen, and exit out. What am I missing here?
Title: Re: Single Switch, Homing + Limits
Post by: dude1 on August 01, 2015, 12:39:57 AM
ask on the ESS forum Andy has a way around it or Steve Stallings may know a way around it, it`s a problem that has come up before
Title: Re: Single Switch, Homing + Limits
Post by: royce on August 01, 2015, 12:47:47 AM
I'll be at Steve's CNC meeting this week @ PMDX's HQ and bring the topic up. I'll report back on my findings unless anyone has any more information. BTW, seems there's not a register link on Warp9's site for me to access the forums unless my login information was setup when I purchased the ESS.

**Edit**
After googling "warp9 forums register" it brought me to the page on the third listing.
Title: Re: Single Switch, Homing + Limits
Post by: bob_at_pmdx on August 02, 2015, 01:35:38 AM
Homing is handled almost entirely in the plug-in.  All Mach4 does is tell the plug-in when to start homing each axis.  It then waits for the plug-in to tell Mach4 that homing is done.  It is up to the plug-in to ignore limit switches when necessary (as it is in this case).  So *if* the homing sequence is aborting when it hits the home/limit switch, that is an issue with the ESS plug-in.

As far as being able to jog off of limit switches, the current Mach4 build (2580) appears to have a properly functioning "Limits Override" button in the default screen set (wxMach.set).  In some previous Mach4 builds (I don't remember which ones off hand but I think it was many builds ago), the "Limits Override" button did nothing.  Jogging off of limits switches is partly handled by Mach4 and partly handled by the plug-in, in that the plug-in needs to be aware of limits override being active and ignoring the limit switch function (our plug-in disabled Mach4 on limit switch trigger except when override is active).  If you see a message in the Mach4 error/status line saying something like "can't job towards X--", then Mach4 doesn't think override is active.  If the machine just won't move, or something else happens, then it may be the ESS plug-in.

Bob
PMDX
Title: Re: Single Switch, Homing + Limits
Post by: dude1 on August 02, 2015, 02:06:57 AM
if as bob say`s its the ESS ask look on the ESS forum there is a way around it, I don't know how well it works if, if the work around is still valid