M620.1 syntax

Hi everybody,

I’m working on editing the filament change script to manipulate the order and way the purges are handled.

I’m getting stopped by the lack of documentation of the G and M codes used by Bambulabs and especially the command M620.1 that handles loading/unloading.

Am I missing something? Does anybody have a good grip on how this command works?

Thanks in advance!

Sadly, BBL has not documented the custom gcode they use.
I have been working to decipher what I can and create a list, but I don’t have the information for 620.

M621 and M622 seem to be used to do runtime condition checking for some things, instead of macros that expand in the slicer. For example when you disable the calibration in the print dialog.

M620 appears in the P1P startup code looking like a conditional based on the AMS. However, it could be used for anything given the variations such as M620.1.

I am going to add a poll for getting gcode documented and see if we can push enough to get BBL to listen.

Ya I wish they would release more information also.

You might reach out to DzzD he has been working on the AMS G-code maybe he has some information.

AMS G-code mods