Commands being executed out of order

Hi,

for my 4 axis printer I hacked Marlin and added a new M command (just like setting the fan-speed, i am setting the angle of the new axis). This works very nice, but the problem is that in a G-Code file the command gets executed about 2 layers ahead. I guess that this might be because of the lookahead for circles, but I don't know how to deal with that. Can someone point me into a direction where I can find more information how I can add the feature properly?

In future I will implement it more clean (really as a new axis), but for a first test this was working well enough.

Thank you for your help!

Could you somehow make use of the M400 command to wait for buffer to clear? Or maybe the G4 command would serve. The G Code reference at this wiki suggests that "G4 P0" is equivalent to M400, so it might be an alternative if your firmware does not support M400.

Quote
jbernardis
Could you somehow make use of the M400 command to wait for buffer to clear? Or maybe the G4 command would serve. The G Code reference at this wiki suggests that "G4 P0" is equivalent to M400, so it might be an alternative if your firmware does not support M400.

Thanks, this is a great solution ! I will try that.