BIGTREETECH EBB42 GEN2 V1.0 | CAN/USB Klipper Toolboard

The BIGTREETECH EBB42 GEN2 V1.0 is a new-generation toolboard designed for installation around 42 mm extruder stepper motors. It centralises the motor, heater, fan, sensor and probe connections on the toolhead and communicates with Klipper through CAN BUS or USB.

It features a 64 MHz STM32G0B1 microcontroller, an integrated TMC2209 driver and extensive protection circuitry. Although it shares functions with the previous EBB42 CAN, the GEN2 version uses a different architecture and pinout and requires its own configuration files.

Main features

• Jumper-selectable CAN BUS or USB communication.
• 24 to 28 V input voltage.
• Heater output rated up to 120 W at 24 V, limited to 5 A.
• Two 2-wire PWM fan outputs.
• One 3-wire fan output with tachometer feedback.
• Selectable 5 V or 24 V fan voltage.
• Protected NTC or PT1000 temperature input.
• 2.2 kΩ pull-up on the temperature input.
• Multiplexed MicroProbe, BLTouch or 24 V inductive probe connection.
• RGB, I²C, endstop and filament sensor interfaces.
• Internal sensor for monitoring TMC2209 temperature.

Temperature sensors

The EBB42 GEN2 supports NTC thermistors or directly connected PT1000 sensors. It does not include MAX31865 and therefore cannot directly read a PT100. A suitable external interface can be added, or the EBB42 CAN with MAX31865 can be selected.

Compatibility and installation

The board can be installed in custom printers and Klipper conversions, including Voron, Rat Rig or VzBot-based systems, when the toolhead provides a mount designed for its geometry. It should not be considered a plug-and-play component for a specific printer.

Klipper firmware should be built for STM32G0B1 with an 8 MHz crystal and the selected interface: USB on PA11/PA12 or CAN on PB12/PB13. The bootloader offset must match the installation, particularly when Katapult is used.

The adapter board is a functional part of the installation because it contains protection components that must not be bypassed. CAN and USB are alternative modes and must not be connected at the same time. The EBB42 GEN2 still requires a separate 24 V supply when operating through USB.

The 120 Ω CAN termination resistor should only be enabled when the EBB42 is located at a physical end of the bus.

Enclosed chamber use

The manufacturer reports long-term testing at chamber temperatures up to 75 °C and recommends fan cooling above 60 °C. The acceptable temperature of the complete assembly also depends on mounting, cooling, motor current and the other installed components.

Other available format

For compact 36 mm motors and toolheads, see the BIGTREETECH EBB36 GEN2.