On Tue, Oct 14, 2008 at 07:52:02PM -0400, John Kasunich wrote: > > There is no g-code that will tell EMC2 "do a homing sequence". There is > G28, but that says "go to the home position", assuming that you've > already homed the machine so it knows where that position is.
This confusion is why the documentation calls G28 a "reference position". It doesn't necessarily have anything to do with the home position (aka machine origin). It only corresponds to the origin by default. It's easy and useful to change it to somewhere else using G28.1. Please do not confuse G28 with the process of homing (moving a joint to seek a switch and/or index pulse). They are entirely unrelated. (I know you know this John, I'm just clarifying for everyone.) > It might be a nice feature to be able to automatically issue a home-all > when you go into "machine on", if it isn't already homed. I know a > certain EMC2 developer who was always forgetting to home the Mazak at > the CNC workshop.... I think I met that guy. He seemed very familiar somehow. He was always relieved to have limit switches and "override limits" which works great to recover from this situation. I think the stupid thing he kept doing was issuing a tool change before homing, and the move to tool change position was what hit the limit switch. Of course it was harmless because the machine has full switches and is properly configured. I think it's very important to be able to jog before homing so I would be against an automatic home at machine-on. However I don't see why you should be allowed to do much else but jog. On my BOSS machine you can only jog very (!) slowly before it's homed. It is fast enough for pulling off a limit switch or pulling the tool up out of some screwup after some minor disaster, but that's it. Chris ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
