常用车辆CAN总线通讯协议,大多直接采用SAE-J1939的形式制定。电动汽车首先遇到了电池系统,电机系统等新加入电气需要重新设定PGN码等问题。CAN协议始终处在诸侯割据的状态。在过去的几年中,国家及相关机构也一直在对电动汽车的CAN通讯协议进行研究,希望形成统一的协议体系。统一的CAN协议,首先是零部件供应商的福音。当前主流主机厂,每家都有自己的整车通讯协议,各个供应商,需要根据整车厂的定义,修改零部件的CAN协议。

制定电动汽车的CAN协议,基本的思路是在SAE-J1939的基础上,根据自身电动汽车的需求,做出必要的调整。

Network layer
包含内容:
  • 设计流程
  • CAN通信矩阵设计
  • 网关报文和路由设计
包含内容:
  • 设计流程
  • CAN通信矩阵设计
  • 网关报文和路由设计
通常我们拿到某个ECU的通信矩阵数据库文件,.dbc后缀名的文件。 直接使用CANdb++ Editor打开,可以很直观的读懂信号矩阵的信息。

CAN总线字节序

星期五, 26 03月 2021
Motorola格式与Intel格式
This satellite module reference design is intended for Bluetooth® low energy passive entry passive start (PEPS) and phone as a key / digital key car access systems. The design demonstrates how control area network flexible data rate (CAN-FD) communication capabilities can be implemented with our Bluetooth wireless MCUs for systems that require higher bandwidth in-vehicle networking communications. Further benefits include reduced power consumption in the sleep state, our CAN auto-addressing method for improved manufacturing, connection monitor capabilities for improved Bluetooth localization accuracy and a compact printed-circuit board (PCB) capable of measuring Bluetooth angle of arrival (AoA) and received signal strength index (RSSI).
Ti integrated circuits and reference designs help you design passive entry passive start (PEPS) modules and key fobs that are secure and compact while reducing system power consumption and optimizing RF and vehicle 
 
This CAN Specification consists of two parts, with • Part A describing the CAN message format as it is defined in CAN Specification 1.2; • Part B describing both standard and extended message formats. In order to be compatible with this CAN Specification 2.0 it is required that a CAN implementation be compatible with either Part A or Part B.

FlexCAN Bit Timing Calculation

星期六, 07 07月 2018
The FlexCAN module supports a variety of means to setup bit timing parameters that are required by the CAN protocol.This document gives a basic insight into bit timings relationship and provide easy step-by-step guide to calculate bit timing parameters for desired baudrate.