Extrusion during pause should, somehow, correct E position...

[cakeller98]

(oops this was originally posted as issue in sprinter, my mistake, it should have been here)

During a recent print, I paused because I could see there was a plastic problem, so I homed in X and Y.... of course, the nozzle sitting there oozed etc, so I primed the extruder....

After I resumed, the extruder RETRACTED the amount of extrusion I had extruded to prime.
In other words, when I manually extruded 150mm and then resumed, the next E command was now 150mm backward from where the board thought it was, so it retracts 150mm to get there... (IT IS BAD to retract too much filament, gets soft filament into the pinch-wheel... BAD BAD BAD :) )

On Pause it would be nice if Pronterface PUSHed the XYZE position of the last G-Code sent.
Then when un-pausing POPed that position back by, moving to that stored Z position, then that X/Y, then G92'd that E position!

Ideally... maybe even start with Z + some offset, then drop down to the correct Z after the rest...
G1 Z+2.0,
G1 X Y,
G92 E
G1 Z

---

What do you think?? if this sounds like a good idea - I might give it a shot. If there's a better way to do it, let me know (maybe I'm doing something stupid)

[kliment]

Thanks, I saw it before. It's only a problem for E, because XYZ get
reset on the next move and the firmware knows to adjust acceleration to
match. Saving and restoring E is a very good idea though. I've been
looking into tracking E in printrun anyway, because it's a much better
progress indicator than what we have now. So I recommend we add "save E"
to the pause command and "restore E" to the resume command, and make it
only work when NOT printing from SD, because then we don't know the
current E value. Are you interested in doing this or should I give it a go?

Kliment

On 10/27/2011 02:46 PM, Christopher wrote:

(oops this was originally posted as issue in sprinter, my mistake, it should have been here)

During a recent print, I paused because I could see there was a plastic problem, so I homed in X and Y.... of course, the nozzle sitting there oozed etc, so I primed the extruder....

After I resumed, the extruder RETRACTED the amount of extrusion I had extruded to prime.
In other words, when I manually extruded 150mm and then resumed, the next E command was now 150mm backward from where the board thought it was, so it retracts 150mm to get there... (IT IS BAD to retract too much filament, gets soft filament into the pinch-wheel... BAD BAD BAD :) )

On Pause it would be nice if Pronterface PUSHed the XYZE position of the last G-Code sent.
Then when un-pausing POPed that position back by, moving to that stored Z position, then that X/Y, then G92'd that E position!

Ideally... maybe even start with Z + some offset, then drop down to the correct Z after the rest...
G1 Z+2.0,
G1 X Y,
G92 E
G1 Z

---

What do you think?? if this sounds like a good idea - I might give it a shot. If there's a better way to do it, let me know (maybe I'm doing something stupid)

[cakeller98]

I would LOVE to. Unfortunately, I don't know python much at all, and I don't have the time at the moment..

[cakeller98]

OK I'll give it a shot, and let you know - I found an extension for VS 2010 for python, so I'll see if that helps me "get" the python part.

will keep you posted, if I get stuck, I might pass the ball back to you. If you've already started, sorry I didn't jump on it sooner!

[kliment]

Fixed in current experimental and latest binaries