2 steppers on one axis 5i25 - 7i76

I have some Proximity Switch NPN to use for home/limit switch. Do you guys have any tips on how to wire them up?

On Mesa boards, PNP are the preferred type -- but both me and Rodw have rigged ours with NPN. And by me and Rodw I mean, he did it and I copied him

It requires a pullup resistor. PCW's guidance on the thread below clarified it for me:

forum.linuxcnc.org/27-driver-boards/3191...sheet?start=10#91557

Is this what I need?

2k 1/2w resistor

I hook this up between the power side and the output side of my switch?

I used these: www.arrow.com/en/products/rs01a2k000jb12/vishay

Rodw used a circuit board for his, but I just soldered mine in as a T-splice to the sensor wire before it gets to the input pin. Page 7 of Norbert's holy gospel of 7i76e configuration has a schematic: forum.linuxcnc.org/27-driver-boards/3191...t?limitstart=0#83622

I checked my notes.I used 2.2 k ohms, 1 W on a 24 volt system.
I always intended to use a board as I had so many switches on the gantry it was convenient to use a DB9 cable and distribute to terminal blocks so I had the room to add the resistors which made it real easy to implement.

Finally found a photo



I added a LED to show I had power to the gantry for troubleshooting
Each of the 7 sensors connects to its own 3 input terminal block.
One switch was an ordinary microswitch so no resistor on that one.

I can not home my Y.

Is there anything you can see that is wrong?

I think you are missing the homing sequence settings inyour ini file for each joint

Here is mine with homing switches so just check the docs I linked to earlier for your immediate homing.

If you don't have the home/limit switches installed yet, I believe you'll need to have it configured more like this:

3.13. Immediate Homing
If a joint does not have home switches or does not have a logical home position like a rotary joint and you want that joint to home at the current position when the "Home All" button is pressed in the Axis gui, then the following ini entries for that joint are needed.

HOME_SEARCH_VEL = 0

HOME_LATCH_VEL = 0

HOME_USE_INDEX = NO

HOME_SEQUENCE = 0

HOME equals to HOME_OFFSET


From the 2.8 doc: linuxcnc.org/docs/devel/html/config/ini-homing.html


Added -- I'm not sure but you might need the Y joints to have HOME_SEQUENCE at -1 to synchronize the joints. I haven't been in your current config before, so it's not a combination of settings I've experimented with.

For the two gantry joints you definitely need
otherwise LCNC won't know they are joined together.

I found it was prudent to home the Z (HOME_SEQUENCE = 0) before X (HOME_SEQUENCE = 1) to lift the Z up away from anything fixed to the table before homing the X