DWC Cancel print vs stop/cancel.g

janjoh

Reading about M0/M1/M2 i see that they all list "The firmware finishes any moves left in its buffer." as the first step.
Can that be overridden short of a M999?

Or maybe I am doing things wrong.

I've added a nozzle clean to my startup sequence. This sxtrudes a bit of filament, retracts it, and runs the tool over a wiper. Works kind of nice.

But what I noticed was that when I got a filament sensor error during the extrude the following happened. (See https://forum.duet3d.com/topic/36278/completely-unreasonable-measured-per-revolution )

Pause.g ran, moving the tool to X0Y0 (TIme to tweak that file by the way.)

WHen I then pressed "cancel print" in DWC, the "wipe moves" were executed. (As I suppose they were in the buffer).

What I would like to do is "Cancel print" to actually "Stop what you are doing, without executing remaining moves".

I know that i currently do not have a "cancel.g" (never needed ut until now), but since I read the definition of M0/M1/M2 as the machine will always first work over the buffer and then execute cancel.g ... Not sure what the cancel.g could contain to purge the current queued moves?

I am CERTAIN that this is just me mis-reading / mis-understanding some aspect of all this. But what?

Cura config for "Start Gcode"

M220 S100
M98 P"0:/Macros/PreWipe.g"
M140 S{material_bed_temperature_layer_0} ;Start heating bed
M190 S{material_bed_temperature_layer_0} ;Wait for bed to reach temp before proceeding
M104 S{material_print_temperature_layer_0} ;Start heating extruder;
M109 S{material_print_temperature_layer_0}
M98 P"0:/Macros/BambuWiper.g"
G32
G1 F500 E30

PreWipe.g

if !move.axes[0].homed || !move.axes[1].homed || !move.axes[2].homed
  G28

M564 S0
G1 X0 Y-165 Z-0.0 F4000
T0                         ; Select tool 
M564 S1

if !move.axes[0].homed || !move.axes[1].homed || !move.axes[2].homed
  G28

;G1 Y-150 X0 Z10 F5000
;G30
M564 S0


G1 X0 Y-165 Z-0.0 F2500
T0                         ; Select tool 
G1 X48 Y-165 Z0.2 F500 E35 ; Start WIpe Locatioon (THIS IS THE MOVE THAT CAUSED THE pause DUE TO SENSOR ERROR)
G1 E-30 F2000
G91                        ; Relative Positioning

while true
  if iterations = 22
    break
  G1 X40 Y0.2 F8000
  G1 X-40 Y0.2 F8000
G90                        ;Absolute positioning

G1 Y-150 X0 Z10 F5000
M564 S1

Pause/Stop/Resume.g are all untouched from the config tool.

chrishamm

@janjoh M0 from a file print executes stop.g. If you pause the print via M25 (or via Pause in DWC) and then cancel it using M0, cancel.g is executed. If cancel.g is not present, stop.g is executed as well AFAIR.

janjoh

@chrishamm

Understood. Thanks. So, does that mean that whatever is in cancel.g supersedes whatever may be in the movement buffer?

chrishamm

@janjoh Only pausing (via M25) may reduce the number of moves in the buffer. M0 and several other codes wait for all pending moves to finish first.