Question about R1 in resume.g

I've been working on getting this filament merger working on a Ormerod 2 with Duet 0.6 + DueX4 0.2a
[github.com]

I'm running DC42's firmware, but an older version (I'm thinking 1.09K) - I haven't updated in awhile because I wanted to make sure anything that wasn't working was because of my modifications and not a firmware change. and I've been a bit short on time lately.

So far things are going well, but I'm having issues with the molten plug left in the nozzle blending with the next color, so color changes happen much later than they should - and the colors tend to blend together for a bit... so color changes are not 'crisp' at all. This would work fine if at a certan Z height you wanted to change colors, but changing within a layer is not working at all.

I'm currently thinking that the nozzle will have to go somewhere, purge, get wiped by a blade, and go back to the print.

Ideally I'd like to be able to do this similarly to how pause.g and resume.g work, but have them in tpre/tpost/tfree for each tool.

; Pause macro file
M83					; relative extruder moves
G1 E-4 F2500		; retract 4mm
G91					; relative moves
G1 Z5 F5000			; raise nozzle 2mm
G90					; absolute moves
G1 X0 Y200 F5000	; move head out of the way of the print

; Resume macro file
G1 R1 Z2 F5000	; move to 2mm above resume point
G1 R1			; lower nozzle to resume point
M83				; relative extruder moves
G1 E4 F2500		; undo the retraction

My question is what exactly is R1, and how does that work? Can I have the tool change macro call on G1 R1 Z2 to go above the print where it was when the tool change was called?

Thanks in advance.

Edited 1 time(s). Last edit at 04/19/2016 12:48PM by shadow651.

I think we need to add a new gcode to define the resume point for that to be possible. I'll give it some thought.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42
I think we need to add a new gcode to define the resume point for that to be possible. I'll give it some thought.

In that case it might be good to have something along the lines of 'save current coordinates' , 'goto saved coordinates' and 'goto saved coordinates with delta modifiers'

Quote
shadow651

Quote
dc42
I think we need to add a new gcode to define the resume point for that to be possible. I'll give it some thought.

In that case it might be good to have something along the lines of 'save current coordinates' , 'goto saved coordinates' and 'goto saved coordinates with delta modifiers'

We already have "goto saved coordinates with delta modifiers", that what G1 with the R parameter does. All that is missing is "save current coordinates".

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42

Quote
shadow651

Quote
dc42
I think we need to add a new gcode to define the resume point for that to be possible. I'll give it some thought.

In that case it might be good to have something along the lines of 'save current coordinates' , 'goto saved coordinates' and 'goto saved coordinates with delta modifiers'

We already have "goto saved coordinates with delta modifiers", that what G1 with the R parameter does. All that is missing is "save current coordinates".

Should've realized that's what pause and the whole R parameter was doing behind the scenes.... I thought it might've been a function that said look at the coordinates n lines ago, not counting macro lines

Maybe we could just add a parameter to pause when reached, that only triggers the storage of coordinates, M226 P1 for example could save to R1

Edited 2 time(s). Last edit at 04/19/2016 10:14PM by shadow651.

dc42, any update on this; I know you're quite busy but I'm just wondering

thanks!

I am sorry, I completely forgot about this. I have now added it to the wish list. I'll probably implement it as M114 R# where # is a resume point number.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].