Stuck on Prusa MK3S BioMod G-code

[Cpt. Raymond Holt]

I'm tryna adapt a bioprinting setup from a Prusa MK2 project to my MK3S (running 3.9.0 FW). The modified hardware's all good, but when I generate G-code in Slic3r, run it through the gcode-composer tool, and load it up. But the problem is it just stalls. No movement, just gcode is incomplete popup on the screen. If I tap yes, nothing happens so I'm a little confused. What might be breaking the G-code for MK3S? BTW, I already trimmed out G28 line... I'm stuck I guess, so I would really love input from anyone who's hacked their Prusa for custom prints.

 

[BioMich]

It's a tricky one since the MK3S has some firmware-level differences from the older models, especially with how it handles certain commands and safety features.
A common cause for this kind of behavior is the M112 command / emergency stop, which the MK3S's firmware might interpret differently or be more sensitive to than the MK2.
It's also worth checking the G-code composer tool's output for any M-codes that might be unsupported on the MK3S, or if there's a missing M104 before the print starts.
Even a missing or malformed M140 can cause the printer to pause indefinitely.
Another thing to consider is the firmware's safety timeouts.
If it doesn't see a temperature rise or some other expected event within a certain period, it might just stop and throw an error.
Try double-checking your gcode-composer settings for any MK3-specific options or flags!

 

[DrRayDrew]

Could the issue be that the gcode-composer tool you're using isn't fully compatible with the MK3S firmware? If it's tossing incomplete G-code errors, maybe it's missing start/end sequences MK3S needs?