Tandem Z axis suddenly homing in opposite directions

I'll set it to -1 shortly. Grabbing some dinner.

Is it a problem that Z and one of the other joints is also -1 or can all joints be -1 in theory?

If you wanted Z to home first you would use -1 for Z and higher numbers
for the other axis , using negative numbers for joints that need to be synchronized.
That's why I said you would need to renumber the homing sequence numbers.

For example If Z must home first but X and Y can home at the same time:

Z joints home sequence = -1
Y joints home sequence = -2
X joint home sequence = 2

Check out the docs here
linuxcnc.org/docs/html/config/ini-homing.html#_home_sequence

If I'm reading this right then:
It will home in a order based on the ABSOLUTE value of the sequence numbers.
You can't skip a number.
And tandem pairs should have a negative as Peter pointed out.

I reset the .ini file by hand and put the setting as recommended:

Z joints home sequence = -1
Y joints home sequence = -2
X joint home sequence = 2

restarted LinuxCNC and z travels in opposing directions. I'll try resetting the home travel again to see if that again fixes this albeit temporarily.

*edit* I also start getting the message "cannot jog joint 3 because sequence is syncronized (-1) before homing I've always been able to jog the joints...

Updated ini attached

Hey AgentWD40, good to see you again!

nope, this time when I try that they just switch who homes in the wrong direction for Z.

I think I have gremlins...

"cannot jog joint 3 because sequence is syncronized (-1) before homing I've always been able to jog the joints...

This is a good thing, it means that LinuxCNC has recognized that the z joints are synchronized
and should not be jogged individually. (it also shows that you cannot use -0 as a home sequence number
for synchronized joints)

Do you need to reverse one of the Z joints due to the mechanics?

Bearfood wrote:

Hey AgentWD40, good to see you again!

I'm following your progress with bated breath

I think it's time you bring up halscope or halmeter so you can watch what's going on... (Or) You mentioned you checked the switches with a multimeter, have you traced the signal back to the 7i96 to make sure your connections are good? But again, halmeter time.

I can do that if that's your recommendation. The thing I don't understand is that they were working fine in tandem previously without issue and then suddenly started going in opposing directions and I just can't understand why. I'll change the wiring but this is the first time I've touched the wiring since adding the home limits...

Also when I did the +/- in Linuxcnc it was moving in the right direction.

Okay, I will read up on halmeter tonight and see what fresh hell I'm getting into.

Tried sifting through documentation and youtube the latter of which was unhelpful. I'm not fully understanding halscope but I managed to get to a point that I found the home-z and home-z2 and found that the z2 was true even though it wasn't tripped. Tripping it on and off yeilded sporadic results while home-z was consistent and toggled correctly. Swapped out the switches and now it homes in the proper direction.

Kudo's to you all. It seems like CMorley hit the nail on the head as well but I really appreciate the guidance you guys have all given!

Thank you so much!