Help with M669 etc

luckyflyer

The instructions say this,

When an axis is homed to a low end (minimum) homing switch, the axis is assumed to be at the lower position limit. When it is homed to a high end (maximum) homing switch, it is assumed to be at the upper position limit. Therefore, changing the position limits in the M208 command will move the origin.

I want origin 0.0 to be left rear which would mean that a + movement on the X axes would move the head to the printers left, to the user standing in front of the printer, his right. Also with a + Y command the head would move toward the front of the printer, toward the user.

My motor mapping is Driver 0 = right rear motor = Y, Driver 1= left rear =X, I have changed this from default with M584.

So is my logic flawed on the above points? If not then we proceed to setting the motor directions to achieve the above goal. This is where I start to have problems. I can get 1 axes to go in the correct direction but not the other, change motor direction and the axes change is reversed.

luckyflyer

Been playing with this all day but it's the classic 1 step forward 2 steps back. here is where I'm at . Note mapping changes from above post.

M669 K1 ; select CoreXY mode

; Drives
M569 P0.0 S1 ; physical drive 0.0 goes forwards
M569 P0.1 S1 ; physical drive 0.1 goes forwards
M569 P0.2 S0 ; physical drive 0.2 goes backwards
M569 P0.3 S0 ; physical drive 0.3 goes backwards

M584 X0.0 Y0.1 Z0.2 E0.3 ; set drive mapping, driver 0 = X driver 1 = Y driver 2 = Z driver 3 = Extruder

The X motor is left rear, Y motor = Right.

; Axis Limits
M208 X0 Y0 Z-.2 S1 ; set axis minima
M208 X310 Y310 Z325 S0 ; set axis maxima

; Endstops
M574 X1 S1 P"!io1.in" ; configure active-low endstop for low end on X via pin io1.in
M574 Y1 S1 P"!io2.in" ; configure active-low endstop for high end on Y via pin io2.in
M574 Z1 S1 P"io3.in"

My Y end stop is at printer rear (preferred location)

All of the homes work correctly, using - (negative) movement numbers. All motor movements are correct as per this guide https://duet3d.dozuki.com/Wiki/ConfiguringRepRapFirmwareCoreXYPrinter
All console movements are correct.

But it is still mirrored.

Nuramori

I’d change your y endstop from y1 to y2

OwenD

I'll ask the dumb question...
There's no chance that your slicer is mirroring the model?

luckyflyer

Ok, when I change Y1 to Y2 everything still homes correctly but when I go to console and give Y a positive 1 MM move (endstop is triggered) nothing happens. If I give Y a negative 1 MM move even though the endstop is triggered Y moves in the Negative direction. That is not right. It's like it thinks that the 0 origin is at the front of the printer.

Later I took this to the next level and loaded a print. The print executed until the gantry was commanded to move forward. Same symptom as above, no movement, endstop activated.

luckyflyer

@OwenD said in Help with M669 etc:

I'll ask the dumb question...
There's no chance that your slicer is mirroring the model?

I'm running s3d and have unchecked flip Y build table axes (I'm aware that there are 2 possible places in S3d that control this feature depending on settings) it had no effect, but I'll try it again just to be sure, I'm fighting a cold and at times a little loopy.

luckyflyer

Flipping Y build table axes in s3d makes no change in the print no matter the setting. It's like the firmware is suppressing the change.

Danal

@luckyflyer said in Help with M669 etc:

Flipping Y build table axes in s3d makes no change in the print no matter the setting. It's like the firmware is suppressing the change.

Compare the gcode files produced.

luckyflyer

dc42 , I have trouble visualizing this statement in my minds eye "The important thing is that viewed from above, +Y is 90deg anticlockwise from +X. Can someone rephrase this or better yet, for us weak minded draw a picture, thanks.

luckyflyer

Got to take about 1 hour break, Downs syndrome son requires we play games on Saturday night.

luckyflyer

@Danal said in Help with M669 etc:

@luckyflyer said in Help with M669 etc:

Flipping Y build table axes in s3d makes no change in the print no matter the setting. It's like the firmware is suppressing the change.

Compare the gcode files produced.

Thats a good idea.

A Former User

@luckyflyer said in Help with M669 etc:

"The important thing is that viewed from above, +Y is 90deg anticlockwise from +X

https://en.wikipedia.org/wiki/Cartesian_coordinate_system#Three_dimensions

and a bit further down https://en.wikipedia.org/wiki/Cartesian_coordinate_system#In_three_dimensions

luckyflyer

Aah yes I get it now, thanks bearer.