config two motor on gantry axis (Y) to square the machine

If two slaved joints are set up, one with a Home offset of -10 the other with -10.253

Is this a setting or hardware switches setup differently?

CNCFred wrote:

If two slaved joints are set up, one with a Home offset of -10 the other with -10.253

Is this a setting or hardware switches setup differently?

Its a setting in your ini file.

rogerxue wrote: Thanks, how do I update to 2.9? do I need to compile myself?

Simplest way is via the buildbot.
buildbot.linuxcnc.org

(point Synaptic at the buildbot repository and install the pre-built packages)

Todd Zuercher wrote: Yes
and
Yes

Home (or home position) sets the point where the axis will rapid to and park at the end of the home cycle. Home Offset sets the value given to the point where the home switch is triggered.

So if your switch is at the negative end of travel, and you set the Home Offset = -10
and Home = 0 the joint will home to the switch and rapid move to 10 units away from the switch and that point will = 0.

If two slaved joints are set up, one with a Home offset of -10 the other with -10.253. Both joints will move to their switches, touch off, (which ever one finishes it's touch first will then wait for the other), then both joints will rapid together to the Home = position.

Can this be achieved with both switches using the same input or to they have to have separate input pins?

I guess they need to be different, pair one of them up with Z,X .

How should the system know which one triggered first? when both are moving towards the home switches?

You could (with the correct HAL and INI config) use only two input pins for X, Y1, Y2 and Z. But Y1 and Y2 need to be different pins.