Скачать или смотреть Bi-directional CAN Bus example

This is a short video of a BeagleBone Black communicating with an STM32F4 Discovery board via CAN Bus. Code is available at https://github.com/mvollrath/canbus_b...

CAN Bus is a communications standard commonly used to integrate sensors, microcontrollers, and computers as a distributed system. Any device on the bus can broadcast or receive messages from all other devices on the bus.

In this example, each synchronized blinking LED pair is controlled by a counter message. One is incremented by a timer on the BeagleBone, the other by a timer on the STM32.

Signals and interrupts are used to avoid polling and minimize CPU profile. The BeagleBone uses signals with a blocking pause(), while the STM32 uses interrupts with a blocking WFI.

The BeagleBone is running on Ubuntu Linux, while the STM32 is using a binary implementing the STM standard peripheral library flashed by the wonderful stlink tool: https://github.com/texane/stlink

The breadboard is home to a couple of TI SN65HVD230 CAN Bus transceivers connected by a twisted pair of wires. The bus operates at 500kbps and has a maximum bus length of 100 meters at this speed. Chip power inputs are guarded by 100nF ceramic bypass capacitors and the CAN lines are terminated by 120ohm 1/2W resistors.