Breakout CAN bus, alim du bus - 3V3 - SPI

Breakout CAN bus for 3V3 microcontroler - MicroPython compatible

Need to connect your board to a CAN bus? Here's a breakout board with an MCP2515 (CAN over SPI bus controller) that allows your 3.3V logic microcontroller to connect to a CAN bus. With two breakout boards, you can even create your own CAN bus from two breakouts.

The   CAN bus is a small-scale network standard originally designed for cars to enable information exchange between different modules. Today, this bus is used in numerous robotics and industrial applications. It's common to find a CAN bus behind a sensor network.

The advantage of the CAN bus is that it has a much better range and addressing capability than the I2C bus. CAN is also based on a differential signal, making it ideal for long-distance communication and noisy environments. The CAN bus is an attractive alternative to Ethernet, which demands too many resources from a microcontroller.

The CAN nessages (64 bits) can be sent at a data rate of 1 Mbps on the bus.
This data rate can be reduced for longuer buses (1 Mbps = 40 m, 500 kbps = 100 m, 250 kbps = 250 m, 125 kbps = 500 m, 50 kbps = 1 km).
All nodes joining the CAN bus must use the same data rate and already have their own address (11 bits for CAN2.0a, 29 bits for CAN2.0b).
Adding a node to the bus is therefore relatively simple, requiring only two parameters (data rate and address) and connecting two wires to join an existing bus.

The CAN protocol allows each node to send its messages whenever it wants. The protocol's implementation enables collision detection and automatic message retransmission in case of failure. Finally, and importantly, in collision event, the node with the lowest address has priority.

This breakout board uses an SPI bus to communicate with the microcontroller. The MCP2515 is a popular component that is supported on many platforms, including Arduino, MicroPython, and CircuitPython. We offer support and documentation support and documentation for MicroPython.

If, despite the documentation, you are still not comfortable with CAN, the internet is full of high-quality, accessible tutorials on the CAN bus.

Technical details

• Alimentation: 3V3
• Logiqque: 3V3
• MCP2515 CAN controler
• TJA1051 CAN transceiver
• ESD protection
• Terminator resistor (activated by default, breakable jumper cavalier sectionnable)
• Circuit d'alimentation step-up 5V pour alimentation du bus CAN
• Size: 52x24mm