Yet another core xy inversion of the y axis

I've read many posts on this, tried the suggestions, but still have a Y axis homing problem on a core XY configuration

Looking from the front of the printer:
- X:0, Y:0 should be front left.
- X:Max, Y:Max should be right rear.

After moving/flipping a few cables, this is mostly working from PrintRun. Y+ commands move the carriage towards the rear. X+ commands move the carriage to the right. But when I click Y Home, it moves to the rear instead of the front. I think it has to be a software setting, but not sure where to look. I would expect Y- and Y Home from PrintRun to move in the same direction.

Configuration.h in Marlin is confusing as X and Y lose their meaning in a Core XY setup. It would be nice if Configuration.h included files specific to the specified geometry so X, Y or A, B have real meaning.

Any help appreciated.

Its still the same as a Cartesian... just ignore that both motors are moving.

Im guessing your #define Y_HOME_DIR -1 is set to 1, which would home to max.

Edited 1 time(s). Last edit at 02/16/2017 11:16PM by Dust.

No, they are all set to -1:

// ENDSTOP SETTINGS:
// Sets direction of endstops when homing; 1=MAX, -1=MIN
// :[-1,1]
#define X_HOME_DIR -1
#define Y_HOME_DIR -1
#define Z_HOME_DIR -1

printrun has an option to home to min or home to max.

Some more information, debug information on the gcodes sent by PrintRun:

1. Moving the Y axis +10mm (towards the rear of the printer)
SENT: G91
SENT: G0 Y10.0 F3000
SENT: G90
SENT: M114
RECV: ok
RECV: ok
RECV: ok
RECV: X:3.00 Y:40.00 Z:0.00 E:0.00 Count A: 2642 B:-2162 Z:0
RECV: ok
SENT: M105
RECV: ok T:0.0 /0.0 B:16.8 /0.0 B@:0 @:0
SENT: M105
RECV: ok T:0.0 /0.0 B:16.9 /0.0 B@:0 @:0
SENT: G91
SENT: G0 Y10.0 F3000
SENT: G90
SENT: M114
RECV: ok
RECV: ok
RECV: ok
RECV: X:3.00 Y:50.00 Z:0.00 E:0.00 Count A: 3442 B:-2962 Z:0
RECV: ok

2. Home the Y Axis. Carriage moves toward the rear of the printer. Should move to the front.
SENT: G28 Y0
SENT: M114
SENT: M105
RECV: echo:busy: processing
RECV: echo:busy: processing
RECV: echo:busy: processing
RECV: echo:busy: processing
RECV: echo:busy: processing
RECV: X:3.00 Y:340.00 Z:0.00 E:

Also, from the LCD panel (Marlin 1.1.0 RC6) if I select Auto Home, it first correctly homes the X axis all the way to the left, then attempts to home the Y axis to the rear of the printer, at which time I have to power the printer off

Interestingly, when I attempt AutoHome from the LCD, and the carriage is moving the Y in the wrong direction, manually engaging the Y endstop switch does NOT stop the movement, I need to kill the power. When using M119, I can verify that all of the endstop switches are working properly. Does this mean that the firmware is looking for a Y-MAX endstop closure?

Quote

Does this mean that the firmware is looking for a Y-MAX endstop closure?

It's worth a try. Just plug the endstop in y-max port and test manually.

on newer marlins there is now a section to define which plugs to use

// Specify here all the endstop connectors that are connected to any endstop or probe.
// Almost all printers will be using one per axis. Probes will use one or more of the
// extra connectors. Leave undefined any used for non-endstop and non-probe purposes.
#define USE_XMIN_PLUG
#define USE_YMIN_PLUG
#define USE_ZMIN_PLUG
//#define USE_XMAX_PLUG
//#define USE_YMAX_PLUG
//#define USE_ZMAX_PLUG

Make sure this matches what you have used.

Yay SUCCESS! Thanks Dust, that was it. I commented out all of the MAX plugs and it works. Guessing it was trying to do YMAX and then YMIN. Interestingly, for X & Z it went to MIN first.