The Original Prusa XL is equipped with multiple electronic boards. The number of boards depends on the number of tools.
The slots on the electronic boards have a label near them indicating the component to connect to each slot.
Printer Rear
Sandwich board
The Sandwich board is the main board with PCIe slots for other boards (e.g. XLBuddy), as well as connectors for many of the printer components, including motors, tool heads, LCD, and others.
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XLBuddy board
The XLBuddy board is the main control board of the printer. It is slotted into the sandwich board. The antenna cable is connected to it.
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XL Splitter board (five-head)
The five-head version of the XL is equipped with the XL Splitter board. The Dwarf boards for Nextruders 3, 4, and 5 are connected to it. The board is slotted into the Sandwich board.
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Tool head
Dwarf board
Each tool is equipped with its own control board, the Dwarf board. An XL printer has as many Dwarf boards as there are tools. All the components that control each Nextruder are connected to its respective Dwarf board.
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Cheese board (multi-tool)
On multi-tool versions of the Original Prusa XL (dual-head, five-head) each tool is equipped with its own Cheese board. This includes a circuit board, 3 hexagonal positioning pins, 2 carrying pins, and 2 nozzle LEDs.
The Cheese board is part of the Tool Changer mechanism. Once the pins are removed, we are left with the Cheese board. Below is a drawing of the Cheese board from the rear and the front.
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Modular bed board
The Modular bed board is located under the heatbed, and controls the heatbed and its tiles. All heatbed segments are plugged into this board.
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