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2-CH CAN HAT, SPI interfaces





2-Channel Isolated CAN Bus Expansion HAT For Raspberry Pi, MCP2515 + SI65HVD230(or SN65HVD230) Dual Chips Solution, Multi Onboard Protection Circuits.



This is a 2-Channel CAN bus expansion HAT designed for Raspberry Pi, supports CAN2.0, features multi onboard protection circuits, high anti-interference capability, and stable operation. It suits for fields such as automotive devices or industrial automation.


  • Standard Raspberry Pi 40PIN GPIO extension header, supports Raspberry Pi series boards.
  • Adopts MCP2515 and SI65HVD230(or SN65HVD230) dual chips combined solution, allowing 2-channel CAN communication.
  • Integrated power isolation, providing stable isolated voltage, requires no extra power supply for the isolated terminal.
  • Onboard digital isolator, signal isolation makes the communication safer, more stable, and better anti-interference.
  • Onboard TVS (Transient Voltage Suppressor) diode, provides ESD protection and transient peak voltage protection.
  • Onboard voltage translator, select 3.3V/5V operating voltage by jumper.
  • Onboard 120Ω terminal resistor, configured by jumper.
  • Breakout SPI control pins, for connecting with host control boards like STM32/Arduino.
  • Comes with development resources and manual.


  • CAN controller: MCP2515
  • CAN transceiver: SI65HVD230(or SN65HVD230)
  • Communication interface: SPI
  • Operating voltage: 5V
  • Logic level: 3.3V/5V
  • Dimensions: 65.0 x 56.5 mm


CAN bus

PIN Raspberry Pi
Raspberry Pi
5V 5V 5V 5V Power input
MISO 9(MISO) 13(MISO) SPI clock input
MOSI 10(MOSI) 12(MOSI) SPI data input
SCK 11(SCLK) 14(SCLK) SPI data output
CS_0 8(CE0) 10(CE0) CAN_0 chip select
INT_0 23(Default)/22 6(Default)/5 CAN_0 interrupt output
CS_1 7(CE1) 11(CE1) CAN_1 chip select
INT_1 25(Default)/24 4(Default)/3 CAN_1 interrupt output


INT_0 is soldered by PIN23 by default, and INT_1 is soldered by PIN25 by default. 
If you need to modify the pins, you need to modify the soldering pad of the PCBA board, and also modify the setting of /boot/config.txt.
Take the modification of INT_0 as an example: if PIN23 is changed to PIN22, then the soldering pad of the red frame on the left board in the figure below need to be modified to the soldering pad of the board on the right in the figure below
Similarly, if you need to change INT_1 from the default PIN25 to PIN24, you need to solder the 0 ohm at the arrow of PIN25 to PIN24.

CAN bus

CAN module could process packets transmit/receive on CAN bus. Packets transmit: first store packet to related buffer and control register. Use SPI interface to set the bits on control register or enable transmit pin for transmitting. Registers could be read for detecting communication states and errors. It will first check if there are any errors of packets detected on CAN bus, then verify it with filter which is defined by user. And store packet to one of buffers if it has no errors.
Raspberry Pi cannot support SPI bus, so this module use SPI interface and on board a receiver/transmitter for CAN communication.
Microchip Technology’s MCP2515 is a stand-alone Controller Area Network (CAN) controller that implements the CAN specification,version 2.0B. It is capable of transmitting and receiving both standard and extended data and remote frames. The MCP2515 has two acceptance masks and six acceptance filters that are used to filter out unwanted messages, thereby reducing the host MCUs overhead. The MCP2515 interfaces with microcontrollers (MCUs) via anindustry standard Serial Peripheral Interface (SPI), that is Raspberry Pi can communicate with MCP2515 via SPI interface without external driver. What we need todo is to enable the kernel driver on devices tree. For more details, please refer to datasheet.

Note: Since October 2021, due to the lack of stock of the SN65HVD230 chip and the price increase, the chip has been replaced with SI65HVD230, and the software and hardware functions are compatible.

SN65HVD230 from TEXAS INSTRUMENTS is a CAN transceiver, which is designed for high communication frequency, anti-jamming and high reliability CAN bus communication. SN65HVD230 provide three different modes of operation: highspeed, slope control and low-power modes. The operation mode can be controlled by Rs pin. Connect the Tx of CAN controller to SN65HVD230’s data input pin D, can transmit the data of CAN node to CAN network; And connect the RX of CAN controller to SN65HVD230’s data input pin R to receive data.

Working with Raspberry Pi

The working voltage level of Raspberry Pi is 3.3V, therefore we need to set the VIO of 2-CH CAN HAT to 3.3V as below:
Note: When connecting to the Raspberry Pi 2b, 3b and 4b boards, please connect the booster and nylon post to fix it to avoid the back of the CAN terminal touching the HDMI interface causing a short circuit, and avoid wrong connection or poor contact:
2-CH CAN HAT 010.png
When connecting to the Raspberry Pi, you must add a booster seat, and then pass the needle through the bottom plate, the effect is as follows:
2-CH CAN HAT 020.png

Enable SPI interface

  • Open terminal, use command to enter the configuration page
sudo raspi-config
Choose Interfacing Options -> SPI -> Yes  to enable SPI interface

RPI open spi.png
Reboot Raspberry Pi:

sudo reboot

Please make sure that SPI interface was not used by other devices, you can check in the /boot/config.txt

Install libraries

  • bcm2835

Open terminal and run commands below to install bcm2835 library

wget http://www.airspayce.com/mikem/bcm2835/bcm2835-1.60.tar.gz
tar zxvf bcm2835-1.60.tar.gz 
cd bcm2835-1.60/
sudo ./configure
sudo make
sudo make check
sudo make install
# For More:http://www.airspayce.com/mikem/bcm2835/
  • wiringPi
sudo apt-get install wiringpi
#When used on Raspberry Pi 4B, you may need to upgrade first:
wget https://project-downloads.drogon.net/wiringpi-latest.deb
sudo dpkg -i wiringpi-latest.deb
gpio -v
# Run the command "gpio -v". If the version 2.52 is displayed, the installation is successful
  • Python

Install python library

sudo apt-get update
sudo apt-get install python-pip
sudo apt-get install python-pil
sudo apt-get install python-numpy
sudo pip install RPi.GPIO
sudo pip install spidev
sudo pip2 install python-can
sudo apt-get update
sudo apt-get install python3-pip
sudo apt-get install python3-pil
sudo apt-get install python3-numpy
sudo pip3 install RPi.GPIO
sudo pip3 install spidev 
sudo pip3 install python-can


Insert the module to Raspberry Pi, and then modify config.txt file:

sudo nano /boot/config.txt

Append these statements to the file:

  • Save and exit, then restart your Pi:
sudo reboot
  • After restart, check if initialize successfully:
dmesg | grep spi


  • Set up CAN:
sudo ip link set can0 up type can bitrate 1000000
sudo ip link set can1 up type can bitrate 1000000
sudo ifconfig can0 txqueuelen 65536
sudo ifconfig can1 txqueuelen 65536
  • For more information about CAN kernel instructions, please check:
  • Run "ifconfig":



If there is only one 2-CH CAN HAT on hand, you can connect CAN0_H and CAN1_H and CAN0_L and CAN1_L of the module as shown in the following figure:

  • install can-utils:
sudo apt-get install can-utils
  • Open two terminal windows:

One terminal input receives CAN0 data command:

candump can0

Another terminal input sends CAN1 data command:

cansend can1 000#
  • The demonstration effect is as follows: (receiving on the left, sending on the right)

If you have two 2-CH CAN HAT on hand, you can directly connect CAN_H and CAN_L two by two. The effect is the same as the above, pay attention to match the communication rate, identify the ID, and output the interface serial number.

Python example

  • Enter the direcory of python example:
  • Run the receiver.py script in receiver terminal:
sudo python reveive.py
  • Run the send.py script in sender terminal:
sudo python send.py

【Note】 The CAN1 is used as sender, and CAN0 is used as receiver.

Codes analysis

【Python example】

The demo codes provided is based on python, please check that if you installed the python-can library.
Before you send data, you should create a CAN device firstly,

os.system('sudo ip link set can0 type can bitrate 100000')
os.system('sudo ifconfig can0 up')

This code is used to initialize CAN0 as receiver/sender. If you want to change it to CNA1, you can use this one:

os.system('sudo ip link set can1 type can bitrate 100000')
os.system('sudo ifconfig can1 up')
  • Connect to CAN BUS
can0 = can.interface.Bus(channel = 'can0', bustyp = 'socketcan_ctypes')
  • or
can0 = can.interface.Bus(channel = 'can1', bustyp = 'socketcan_ctypes')
  • Create message

msg = can.Message(arbitration_id=0x123, data=[0, 1, 2, 3, 4, 5, 6, 7], extended_id=False)
  • Send message
  • or:
  • Finally, close CAN device
os.system('sudo ifconfig can0 down')
  • or:
os.system('sudo ifconfig can1 down')
  • Receive message:
msg = can0.recv(10.0)

The variables of recv() function is the timeout of receving.
For more information, please refer to:https://python-can.readthedocs.io/en/stable/interfaces/socketcan.html

【WringPi example】

  • Blocking the reception, the Raspberry Pi opens the terminal and runs::
cd 2-CH_CAN_HAT_Code/wiringPi/receive/
make clean
sudo make
sudo ./can_receive
  • Raspberry Pi opens the terminal and runs:
cd 2-CH_CAN_HAT_Code/ wiringPi/receive/
make clean
sudo make
sudo ./can_send




3D Drawing


No, it only supports the Raspbian system.

You can try to update the kernel version:
sudo apt update
sudo apt upgrade
uname -a

If the initialization fails, you can restart the Raspberry Pi or other main control platform development boards to ensure that the connection is correct, refer to the wiki to carefully check whether there is any leakage in the configuration and whether the logic voltage jumper pin is selected correctly.

The chip is affected by many factors such as the surrounding environment, communication distance, wires, software and so on. During high-speed communication, the data baud rate may not reach the nominal maximum rate. Users need to ensure stability and select a suitable communication speed according to actual measurements.

If the initialization is successful and the speed is set properly, it still cannot communicate normally. Please check whether the CAN_H of the next two 2-CH CAN HATs is connected to another CAN_H, and whether CAN_L is connected to another CAN_L. It should be noted that these two lines cannot be reversed. H corresponds to H, and L corresponds to L. If there is no problem, please check whether the CAN port configured by the program is correct. For example, CAN0 is required, but the program code configures CAN1. At the same time, it is also necessary to check whether the hardware is connected correctly and whether there is a short circuit in the CAN interface. As shown in the figure below, the CAN interface and the HDMI interface of the Raspberry Pi are accidentally connected to cause a short circuit, which makes the CAN unable to communicate normally. At this time, it is necessary to purchase a 2-CH The 2×20PIN long row seat of accessories delivered during CAN HAT will be heightened.

2-CH CAN HAT01.png


If you require technical support, please go to the Support page and open a ticket.