MMU2 doesn't want to change tools during a print, only manually
I just set up my MMU2 (on a MK3S+) and I'm trying to print the first sheep model. I downloaded the sheep and sliced it myself in PrusaSlicer with 2 colours, and I have only loaded the 2 colours in the MMU2. Both colours can feed to the nozzle fine. During the print, the GCODE looks like it tries to do a tool change, but nothing happens and it keeps using the same filament. If I pause the print, unload filament 1 and load filament 2, then resume, everything prints ok. It actually switched back to filament 1 by itself, but then wouldn't switch again.
If I manually send T1, I get this from the printer: T1 seems to switch to T0, is that right? And T2 says 'Duplicate T-code ignored'
I'm not sure what is going on or what I am doing wrong
Send: T1
Recv: mmu_get_response - begin move: T-code
Recv: MMU <= 'T0'
Recv: Unloading finished 2 [...]
Recv: mmu_get_response - begin move: load [...]
Recv: MMU <= 'A'
Recv: MMU => 'ok'
Recv: mmu_get_response() returning: 1 [...]
Recv: MMU can_load:
Recv: OOOOOOOOOOOOOOOOOOOOOOOOOOOOOO succeeded.
Recv: ok [...]
Send: T2
Recv: Duplicate T-code ignored.
Recv: ok
RE: MMU2 doesn't want to change tools during a print, only manually
Follow up to this, I built the MK3S firmware myself from git and without making changes to the code, this problem has gone away. I'm not sure why its fixed or what the problem was but now I see this in console:
>>>T4
SENDING:T4
mmu_get_response - begin move: T-code
MMU <= 'T4'
And filament changes properly during prints.