1. Introduction
The BIGTREETECH EBB36 CAN / EBB42 CAN is a specialized nozzle adapter board designed for 36 and 42 extruder stepper motors, developed by Shenzhen Big Tree Technology Co., Ltd. This board facilitates communication via either a USB port or CAN BUS, significantly simplifying wiring configurations in 3D printing setups. It is primarily intended for connecting Klipper expansion devices.
The U2C module is a USB to CAN bus converter, allowing Raspberry Pi's USB port to interface with CAN bus devices like the EBB boards, offering flexible connectivity options.
2. Key Features
- Firmware Update: BOOT and RESET buttons are reserved for easy firmware updates via DFU mode using USB.
- Thermistor Protection: An integrated protection circuit prevents damage to the main control chip from leakage current originating from the heating rod.
- Configurable Thermistor Pull-up: Jumper wires allow users to select thermistor pull-up resistor values, supporting PT1000 (2.2K pull-up resistors) for DIY convenience.
- USB Power Isolation: A jumper cap can be used to power the board via USB, effectively isolating the main control board's DC-DC converter from the USB 5V supply.
- I2C Interface: Reserved I2C interface supports filament breakage and clogging detection, and other custom DIY functions.
- MOS Tube Protection: Anti-flyback diodes on heating rod and fan ports protect MOS tubes from reverse voltage damage.
- Power Interface Protection: Anti-reverse connection protection on the power interface prevents damage from incorrect power line connections.
- Onboard MAX31865: Supports 2-wire or 4-wire PT100/PT1000 configurations.
- Communication Options: Supports communication via CAN or USB. The 120R terminal resistor for CAN can be selected via a jumper cap, and CAN expansion interfaces are reserved.
- USB ESD Protection: An ESD protection chip on the USB port safeguards the main control board from static electricity.
- DIY Friendly: The adapter board comes with necessary terminals, female reeds, double-way studs, and screws for various DIY projects.
- Onboard Sensor: ADXL345 accelerometer for precise motion sensing.
- Motor Driver: Onboard TMC2209 driver operating in UART mode.
- Microprocessor: ARM Cortex-M0 STM32F072C8T6 48MHz (or STM32G0B1CBT6, chips sent randomly).
3. Setup and Installation
3.1 Board Installation
The EBB36/EBB42 boards are applicable for 35/36/42mm motors. When installing, ensure that the pinhead of the motherboard does not contact any metal surfaces to prevent short circuits.
3.2 Wiring Diagrams
Refer to the following diagrams for proper wiring of the EBB36 CAN and EBB42 CAN boards. Pay close attention to power and signal connections.
3.3 Jumper Settings
- USB Power: Use a jumper cap to connect the USB power input if you intend to power the board via USB. This isolates the main control board's DC-DC from USB 5V.
- CAN Bus Termination (120R): If the EBB board is used as a terminal node in a CAN communication network, ensure the jumper cap is placed at the 120R position to enable the terminal resistor.
- Thermistor Pull-up Resistors: Select the appropriate pull-up resistor values via jumper wire. For PT1000 thermistors, use 2.2K pull-up resistors.
- PT100/PT1000 Configuration: The onboard MAX31865 supports both 2-wire and 4-wire PT100/PT1000. Configure this via jumpers as needed.
3.4 U2C Module Integration
The BIGTREETECH U2C module allows a Raspberry Pi to communicate with the EBB boards via CAN bus. Below is a diagram illustrating the connection between a Raspberry Pi, U2C, and an EBB board.
3.5 Firmware
The BIGTREETECH EBB36/EBB42 CAN boards currently support Klipper firmware. Firmware updates can be performed via DFU mode using the USB port and the dedicated BOOT and RESET buttons.
4. Operation
4.1 Communication
The EBB boards can communicate with your main control board via either USB or CAN BUS. CAN BUS offers long data transmission, strong anti-noise ability, real-time performance, and high reliability.
4.2 Fan Control
The boards feature two CNC fan interfaces (FAN0, FAN1) with a maximum output current of 1A (peak 1.5A). Some versions, like GEN2, may include an additional 3-pin fan (FAN2) with tachometer feedback. Ensure correct power selection for fans if applicable.
4.3 Expansion Interfaces
The EBB boards provide various expansion interfaces for enhanced functionality:
- EndStop: For limit switch connections.
- I2C: For filament sensors (break/clog detection) and other I2C devices.
- Probe: Supports various probes (Multiplexed Microprobe, BLTouch, 24V Probe port).
- RGB: Reserved port for illumination.
- PT100/PT1000: For high-accuracy temperature sensing.
- USB Interface: For direct connection and DFU mode.
- CAN Interface: For robust communication with Klipper expansion devices.
5. Maintenance and Safety
The EBB boards are designed with several protection features to ensure longevity and safe operation:
- Thermistor Protection Circuit: Prevents damage to the main control chip.
- Anti-flyback Diodes: Protect MOS tubes on heating rod and fan ports from reverse voltage.
- Anti-reverse Connection Protection: Safeguards the motherboard from incorrect power input.
- ESD Protection Chip: On the USB port to prevent static electricity damage.
- Surge Protection: Additional protection against power surges.
General Care: Always handle the board with care. Avoid contact between metal objects and exposed pins or components to prevent short circuits. Ensure all connections are secure before applying power.
6. Troubleshooting
- No Power/Board Not Responding:
- Verify input voltage (DC12V-DC24V) and ensure correct polarity. Reversing 12/24V and GND can damage the board.
- Check USB power jumper settings if powering via USB.
- Ensure all cables are securely connected.
- CAN Bus Communication Issues:
- Confirm that the 120R terminal resistor jumper cap is correctly placed if the EBB board is a terminal node in the CAN network.
- Check CAN-L and CAN-H connections for proper wiring.
- Ensure Klipper configuration for CAN bus is correct.
- Thermistor Reading Errors:
- Verify the thermistor type (PT100/PT1000/NTC) and ensure the correct pull-up resistor jumper settings are applied (e.g., 2.2K for PT1000).
- Check thermistor wiring for shorts or open circuits.
- Firmware Update Failure:
- Ensure the board is in DFU mode (using BOOT and RESET buttons) before attempting a USB firmware update.
- Check USB cable and connection.
For more detailed troubleshooting and advanced configurations, please refer to the official BIGTREETECH GitHub repository: https://github.com/bigtreetech/EBB
7. Specifications
| Feature | Specification |
|---|---|
| Item Type | Motherboard |
| Model Number | EBB36 EBB42 CAN |
| Microprocessor | ARM Cortex-M0 STM32F072C8T6 48MHz (or STM32G0B1CBT6 64MHz for GEN2, chips sent randomly) |
| Communication Method | CANBUS, USB |
| Input Voltage | DC12V-DC24V 6A (Mainboard) / DC12V-DC24V 9A (General) |
| Logic Voltage | DC 3.3V |
| Heating Interface (E0) | Maximum output current: 5A (96W @ 24V / 4A for GEN2) |
| Onboard Sensor | ADXL345 |
| Motor Drive | Onboard TMC2209 UART |
| Fan Interfaces | Two CNC fans (FAN0, FAN1), some GEN2 versions have a 3-pin FAN2 with tachometer feedback. |
| Max Output Current (Fan) | 1A, Peak Value 1.5A (Total for GEN2) |
| Expansion Interfaces | EndStop, I2C, Probe, RGB, PT100/PT1000, USB Interface, CAN Interface |
| Temperature Sensor Interface | 1 Channel 100K NTC or PT1000 (TH0), 1 Channel PT100/PT1000 |
| USB Communication Interface | USB-Type-C |
| DC 5V Maximum Output Current | 1A (Peak 1.5A for GEN2) |
| External Dimensions (EBB36) | 51.5mm x 37mm |
| Installation Dimensions (EBB36) | Hole spacing 43.85mm, M3 screw hole x 2 |
| External Dimensions (EBB42 GEN2) | 45mm x 40mm (1.77in x 1.57in) |
| External Dimensions (EBB36 GEN2) | 43.85mm x 42.92mm (1.73in x 1.69in) |
7.1 Model Comparison: EBB 36&42 GEN2 vs. EBB 36&42 CAN
The following table highlights key differences between the GEN2 and CAN versions of the EBB boards:
| Feature | EBB 36&42 GEN2 | EBB 36&42 CAN |
|---|---|---|
| Communication type | CAN & USB | CAN |
| Communication passthrough | Adaptable CAN or USB via JST | CAN via berg header |
| Chamber temperature | 75°C | Not recommended above 65°C |
| Cable included? | ✓ | ✗ |
| Cable type | Shielded with drag chain rated strands and coating | N/A |
| Protection schemes | Input power over current and reverse voltage. All FETs are automotive grade with over temp and over current protection. Short-circuit protection on data communication inputs. Momentary short-circuit protection on all I/O. Thermistor short-circuit protection on and ESD Protection on motors and all exposed I/O. Electrostatic buildup drainage via mounting holes. | Input power over current and reverse voltage. |
| Main connector type | XT30(2+2) | MX3.0/5557-2X2 4P |
| Tacho feedback on hotend fan | ✓ | ✗ |
| Side accessible buttons? | EBB36 GEN2 - Convenient side access, EBB42 GEN2 - Convenient front access | N (front, middle access) |
| Heatsinks on MCU, and USB hub? | ✓ Heatsinks included for user application | Only on driver |
| Supports 1080p nozzle camera? | ✗ | ✗ |
| Voltage selection on all fans? | All fans support 5V or 24V selection via jumpers | Only supports 24V |
| Thermistor for direct driver temperature measurement? | Placed directly beneath driver for accurate temperature measurement | None |
8. User Tips
- Prevent Short Circuits: Always be cautious during installation to ensure no metal parts come into contact with the motherboard's pinheads.
- CAN Bus Configuration: When setting up CAN communication, identify if your EBB board is the terminal node. If so, remember to install the jumper cap at the 120R position.
- Firmware Updates: Utilize the dedicated BOOT and RESET buttons for reliable firmware updates via DFU mode over USB.
- Thermistor Compatibility: If using a PT1000 thermistor, ensure the correct 2.2K pull-up resistors are selected via the jumper wires for accurate temperature readings.
- Power Polarity: Double-check the polarity of your 12V/24V power supply before connecting to avoid damaging the board.
9. Warranty and Support
For technical support, detailed documentation, and the latest firmware, please visit the official BIGTREETECH GitHub repository:
https://github.com/bigtreetech/EBB
Information regarding specific warranty terms is typically provided at the point of purchase or on the seller's official website. Please consult your vendor for warranty details.
