README.md

Controller Area Network (CAN)

This directory contains assembly language examples related to CAN.

CAN Controller/Peripheral example

This examples uses two stm32 boards and two CAN transceivers to enable the transmission of data from the controller, can-c.s to the peripheral, can-p.s.

Building

$ make can-c.elf can-p.elf

Flash and Run the peripheral

Connect the USB micro cable to the STM32 ST-LINK port on the board that is going to be used as the peripheral.

Start openocd:

$ make openocd

Start a telnet session:

$ telnet localhost 4444

Flash the program:

> reset halt 
> flash write_image erase can-p.elf.hex
> reset run

Flash and Run the controller

Connect the USB micro cable to the STM32 ST-LINK port on the board that is going to be used as the controller.

Start openocd:

$ make openocd

Start a telnet session:

$ telnet localhost 4444

Flash the program:

> reset halt
> flash write_image erase can-c.elf.hex
> reset run

Start minicom:

$ minicom --baudrate 115200 --device /dev/ttyUSB0

Next press the reset button on the controller board and 'A7' should be displayed in minicom. The A is the data sent to the CAN bus and 7 is the identifier of the CAN frame.

CAN loopback example

This example can be run without any external transceiver or wires connected (wires for CAN that is) and use the CAN loopback to send and receive data. The received data is then sent using UART so that it can be inspected using minicom.

Building

$ make can-loopback.elf

Flash and Run

First start openocd:

$ make openocd

Start a telnet session:

$ telnet localhost 4444

Flash the program:

> reset halt
> flash write_image erase can-loopback.elf.hex

Start minicom:

$ minicom --baudrate 115200 --device /dev/ttyUSB0

Next press the reset button and 'A7' should be displayed in minicom. The A is the data sent to the CAN bus and 7 is the identifier of the CAN frame.