After homing X and Y, can I auto move to a non 0,0 location?

I've recently gotten switch-based homing working on my 12"x12" DIY xyz mill.  The mill is the style where the spindle is stationary, and the bed moves in two directions underneath.  (I'm sure there's a name for that.)

0,0 is at the near left corner of the bed (of course), and after homing, with the spindle above that point, the bed is basically as far from me as possible.

I'd prefer it to home to 12,12 instead of 0,0, which would leave the bed as close to me as possible.  I've tried homing against the upper limits instead of the lower limits, with a HOME_OFFSET of 12, thinking that would help, but after homing at the near corner, the mill once again moves all the way to the other end, in order to end up at 0,0.

Is there a way to accomplish what I want?  If I can't convince it to actually home to the near corner, is there a way to automatically invoke an arbitrary move after homing?  

Post your INI file please and we'll see what needs editing.

And yes, homing is a never-ending struggle for LCNC users - both new and old-but-rusty.

Also make sure you read this entire document:

linuxcnc.org/docs/html/config/ini-homing.html#_home

It seems like HOME is the INI variable you need to change.

Thank you both. I'm certain you're right: Home is set to 0. So if I switch to homing at the 12,12 corner, and change HOME to 12 for both X and Y, it will almost certainly do what I want. INI file attached, in any case.   If HOME had been grouped with the other HOME_* variables, I might have noticed. 

I also need to stop using google to find linuxcnc docs, rather than having some known-good bookmarks on hand. Not only does google often point to old versions of the docs, it will also take you into the middle of the document. While I'd read most of the page @PCW linked to, I think I'd never even seen the first several sections, with the excellent colorful diagrams. Wish I had!

Ahh you see the light! Be sure to read the correct version of the documents for the version you are using. Everything you need to know is there in those docs!

Well reading the (correct, even) documentation hasn't helped.

Clearly, my expectations are wrong.  I have an axis that goes from 0 to 12.  I want to home at the "12" end.  It's a "bed moves" mill, so the motions are all backwards from the POV of the config, which is clearly expecting a "spindle moves" mill.  

Here's what I have.  The SEARCH and LATCH phases work fine, both searching negative.  But when the axis engages HOME_FINAL_VEL, it also heads in the negative direction to find HOME.  To be clear: HOME_SEARCH_VEL, HOME_LATCH_VEL, and HOME_FINAL_VEL are all moving the axis in the same, negative, direction.

With the INI as shown, it moves .5" before stopping.  (I've replaced "HOME=12" with "HOME=.5" for testing, simply so the axis doesn't move so far in the wrong direction.  I'm testing in the middle of the bed, simulating by activating the limit switch by hand.)

What do I need to do?


 

Just to be sure about this...where are the limit switches physically located in relation to the travels?

With the table all the way back and to the right?

You have to remember you are dealing with cartesian coordinates.
You can home to any corner you wish. Homing to the lower left of the worktable means all x,y coordinates are in the positive quadrant.
Homing to another corner will mean at least one axis will count in the negative direction. Think of the graphs you drew at school

I did have a machine where the home switch was at max Y but I added a home offset to make the home position at min Y
Thinking about it after using it, I realized I could have homed it at the home switch position so the Y axis would count in the negative direction beecause once you zero G54 offsets at lower left on your workpiece, everything would count in a positive direction anyway.

@spumco may be onto something? My limit switches are shared: both switches on one circuit. Maybe that's the problem?

@rodw -- My impression and hope was that if I homed to the upper right, I could somehow let the mill know that that point was 12,12 , and that therefore both axes would, yes, count in the negative direction, but not actually ever be negative. They would still go from 0 to 12, but it wouldn't be the 0,0 corner that homing was finding.
Does that make sense?