基于can总线技术的汽车ecu设计.htm

基于CAN总线的汽车控制器ECU的设计开发实例

style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">控制器芯片</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">SJA1000</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">来组合使用</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">[4][6]</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。由于</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">总线技术应用领域广泛，一些芯片生产厂家（如</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">Motorola</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">、</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">Intel</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">、</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">Philip</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">、</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">Atmel</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">、</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">Microchip</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">以及</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">NEC</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">等公司）纷纷在自己的芯片中集成了</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">接口模块，这样将大大提高</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">接口通信的可靠性。本文采用</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">Atmel</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">公司的一款内嵌</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">控制器的</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">AVR</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">型单片机</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">AT90CAN128</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">来实现</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">节点。</SPAN><SPAN 
lang=EN-US><O:P></O:P></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left"><SPAN 
lang=EN-US><O:P><FONT face="Times New Roman" size=3></FONT></O:P></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left"><FONT 
size=3><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">AT90CAN128</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">单片机具有以下特点：</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">128K</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">字节</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">FLASH</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">4K</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">字节</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">EEPROM</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">和</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">4 K</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">字节的</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">SRAM</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，带有硬件乘法器功能，</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">53</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">个通用的</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">I/O</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">口，</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">32</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">个通用工作寄存器，</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">4</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">个具有比较模式的定时器</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">/</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">计数器，</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">2</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">通道</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">8 </FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">位的</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">PWM</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">6</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">通道</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">2</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">到</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">16</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">位精度的</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">PWM</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">2</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">个</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">USART</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">和</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">1</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">个主从</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">SPI</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">串行口，</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">1</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">个两线</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">( I2C) </FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">串行接口，一个</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">8</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">通道</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">10</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">位具有可选增益差分输入的</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">A/D</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">转换器，</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">1</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">个带内部振荡器的可编程看门狗定时器</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">[10]</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。同时还集成了</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">控制器，与</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">标准帧</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">2. 0A</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">和扩展帧</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">2. 0B</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">完全兼容，具有</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">15</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">个独立的信息对象，能够处理所有的帧类型，具有</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">8</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">位静态分配的数据缓冲区，晶振频率</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">8MHz</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">时数据传送速率可达到</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">1Mbps</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。</SPAN><SPAN 
lang=EN-US><O:P></O:P></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left"><SPAN 
lang=EN-US><O:P><FONT face="Times New Roman" size=3></FONT></O:P></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left"><FONT 
size=3><SPAN lang=EN-US><FONT face="Times New Roman">3.1 </FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">硬件设计</SPAN><SPAN 
lang=EN-US><O:P></O:P></SPAN></FONT></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left"><SPAN 
lang=EN-US><O:P><FONT face="Times New Roman" size=3></FONT></O:P></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left"><FONT 
size=3><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　在本文的设计中，利用</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">AT90CAN128</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">A/D</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">转换器采集相关传感器的电压信号（如水温、振动、位置、气压以及油压等信号），利用定时器</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">/</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">计数器模块采集相关传感器的脉冲信号（如转速、里程等信号），由于</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">AT90CAN128</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">集成了</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">控制器功能，因此，结合</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">总线收发器即可完成</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">总线的接收和发送任务。</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">总线收发器采用了</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">ATA6660</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">芯片，它是</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">CAN </FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">控制器与物理传输媒体之间的物理连接子层接口。为提高系统的抗干扰性，在</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">AT90CAN128</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">与</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">ATA6660</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">芯片之间加入高速光耦芯片</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">6N137</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，其接口电路如图</SPAN><SPAN 
lang=EN-US><FONT face="Times New Roman">2</FONT></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">所示。</SPAN><FONT