The Original Prusa MK4/S, MK3.9/S, and MK3.5/S are equipped with an xBuddy board.
In their factory state, our printers only accept official firmware. To flash any unofficial firmware to the printer, it is necessary to break the appendix on the xBuddy board.
Before attempting this procedure, carefully review the description and the photo below.
To break the appendix, open the electronics box and locate a safety seal on the xBuddy board, with an exclamation mark on it. Then, take a small flathead screwdriver or very thin sharp pliers and break off the thin middle part of the fuse.
Once the appendix is broken, flashing firmware can be done following the procedure in the dedicated article on firmware updating.
If you have a question about something that isn't covered here, check out our additional resources.
And if that doesn't do the trick, you can send an inquiry to [email protected] or through the button below.