How to configure for origin at left REAR (not front) on a Cartesian printer?

GoBig

I'm using Repetier firmware 0.92.9. I have a custom cartesian printer with the origin in the left rear. I see that Repetier expects it to be at the left front. What do I need to change to get the firmware to know the Y origin is in the rear? Everything currently works on the printer except that the Y axis prints the mirror image of what it should. Do I just need to set the following 2 variables:

INVERT_Y_DIR 1

Y_HOME_DIR 1

Since Y_HOME_DIR 1 defines that the endstop is at the max, do I also need to physically connect the Y endstop switch on the controller board to the Y_Max terminals?

Thanks

Repetier

Left rear is not possible with normal orientation of axis. You need to swap x and y motors and endstops and assign homing direction/max min endstop matching your printer. Left-right will then become x axis and back->front x axis.

GoBig

I found a configuration that works. For all others that want to do this configuration, here's what I did:

1. Assuming you have only min endstops, connect the Y endstop to the Y Max terminals on your control board. The rest are firmware changes.

2. Reconfigure endstops

#define ENDSTOP_Y_MIN_INVERTING true

#define MIN_HARDWARE_ENDSTOP_Y false

#define ENDSTOP_Y_MAX_INVERTING true

#define MAX_HARDWARE_ENDSTOP_Y true

3. Reconfigure Y movements

#define INVERT_Y_DIR 1

#define Y_HOME_DIR 1

You do NOT need to change the Y Min value

#define Y_MIN_POS 0 // min still 0, but it is in the front of the printer now

When you home the printer, it will be in the left rear at position x=0, y=Y_MAX, z=0, and it will print correctly.

Repetier

You know that is not what you asked for:-) Origin = 0,0 in your solution is still left front only homing position is now left back!

I now assume that is what you really wanted, so well done!