M117 with quoted string sometimes gives an error

stuartofmt

I monitor my print jobs with messages sent using M117. Usually two messages - one at the start and one at the end of the print job. I have notices some strange behavior.
I'm using R3.3.0 stable.

With both message strings quoted: The first M117 call works but the second generates an error.
With the first quoted and the second not quoted - there is no error.

For case 1 - this is the error (actually 2):

Error: in GCode file line 797 column 9: M117: string too long

Error: in GCode file line 797 column 9: M117: string too long
Finished printing file 0:/gcodes/TinyTest1.gcode, print time was 0h 9m

This is the simple gcode file that demonstrates the error:

TinyTest1.gcode

Remove the quotes on line 797 and there is no error. Line 27 remained quoted in both tests and behaved as expected.

Obviously - the workaround is to not use quotes with M117 but something strange is happening so I thought it best to report.

For completeness stop.g (called via M0 on the line following the error) is attached

stop.g

fcwilt

@stuartofmt

A simple test file of:

M117 "LINE 1"
G4 S5
M117 "LINE 2"
G4 S5

works without issue so something about your actual file is in play.

I will keep testing.

Frederick

stuartofmt

@fcwilt said :

so something about your actual file is in play.

This also happened on a completely different print job (which is where I first noticed it.)
It may be irrelevant - but the gcode was created by the Prusa slicer.

In the morning I will test with your test file to eliminate (or not) further on my side

dc42

@stuartofmt thanks, I have reproduced the issue using your TinyTest file. I will investigate it.

stuartofmt

@dc42

Hopefully this is of help.

Attached are two very minimal fake print files (basically waving the nozzle around in mid air).

The first seems to only produce the error when run the first time but subsequent runs do not produce the error. The second produces the error all the time. See the console grab below.

I tested multiple times with a freshly refreshed machine and new DWC instance

ReallyTinyTest1.gcode
ReallyTinyTest2.gcode

dc42

@stuartofmt thanks, your files were helpful.

I've found the cause of this issue. A workaround is to use M400 immediately before the M117 command.

stuartofmt

@dc42

M400 before M117 is confirmed as working on my end.

Thanks

DonStauffer

@dc42 It seems like having some kind of error shortly before the M117 can make it error. I routinely get that but always when there's some other error within a minute or so before.