Acceleration, bad code generated

[povlhp]

Running 3.2, and I have issues with the genrated gcode when using acceleration from within Cura.

I get code like this:

M204 S2400

M205 X15 Y15

G1 F2700 E60.37217

G1 F300 Z1.3

G0 F3600 X84.044 Y111.972 Z1.3

M204 S2000

M205 X12 Y12

G1 F300 Z0.3

G1 F2700 E65.3888

G1 X87.027 Y111.972 E65.53018

M204 S2400

M205 X15 Y15

G0 F3600 X87.978 Y111.424

Since I am using Marlin, it is possible to set the values once per file, using specific values. See http://marlinfw.org/docs/gcode/M204.html

M204 P2000 T2400

Would set travel to 2400 and print to 2000mm/s^2

As it is, curves are printed very slowly (I am at 115kbps, as I have enabled Linear Advance in FW). With the current implementation, I will not use it. Then it is way better to put the values in header gcode or early on like setting initial layer temps.

[smartavionics]

It would be trivial to make the change you suggest but according to http://reprap.org/wiki/G-code#M204:_Set_default_acceleration, Marlin hasn't always supported the P and T values so I don't know if this can be done without causing a problem with backwards compatibility.

[povlhp]

Correct. It is not in Marlin 1.0.
It is in Marlin 1.1 and forward. So it could cause backward compatibility issues.

My GeeTech MeCreator 2 came with Marlin 1.0.2-2, so it would not be compatible with acceleration control the new way.

So I will just do it in in preamble gcode.

[smartavionics]

Hi, thanks for looking into that. Well, As I said the change is trivial. However, it's not me that makes this kind of decision, we need to involve someone like @Ghostkeeper or some other Ultimaker person.

[povlhp]

smartavionics I mistakenly looked for M205. M204 with P/T was not implemented before 1.1, so doing the change will break backward compatibility.

[smartavionics]

OK, understood. Well, if this can't be done, could you please close the issue? Thanks.

[povlhp]

Closed. Would break backward compatibility.
For Marlin 1.1 and never, set jerk and acceleration in start gcode.