Contributions in can-based systems: prototypes and tests

Abstract

The CAN network is used to connect microcontrollers exclusively through a metal bus and broadcast messages. In versions 2.0A and 2.0B the CAN frame payload carries up to 8 bytes of data. To send larger data it is necessary to use more than one frame. This paper presents a CAN network prototype using six Arduino cards that generate and consume different types of signals connected through the MCP2515 CAN module. The library used to enable the MCP2515 CAN module organizes the 8 bytes of CAN frame payload into an 8-position array, each with 1 byte. Taking advantage of this feature, besides demonstrating how to use this device, some proposals for improvement in the CAN network will also be presented. The first of these is a form of treatment of periodic and aperiodic signs. CAN frame and communication bus utilization has been optimized by sending multiple signals within a single frame, carrying one signal at each position of the vector. Mapping values to intervals compatible with the available space at each vector position allowed the transport of values larger than 8 bits within the vector positions. Transmission latency was calculated using the mills() method and a CAN gateway was implemented to reduce the broadcast domain of messages.