mycan.c

motorola 集成CAN控制器

#include <hidef.h>      /* common defines and macros */
#include <mc9s12d64.h>     /* derivative information */
/*采用9S12D64实现的CAN,发送时while(1){CAN_Transmit();}可实现发送,接收时用中断,接受ID=2的扩展贞，接受的字符用串口发送到计算机显示*/

#define CAN_BUFFER_LNG 64 
uchar CANReceive[CAN_BUFFER_LNG]; 
char i;

 uchar mask;


/* MSCAN初始化*/
void MSCAN_init(void)
{	CAN0CTL1_CANE = 1;  
	CAN0CTL0_INITRQ = 1; 
	while(CAN0CTL1_INITAK!=1); 
	CAN0CTL1_CLKSRC = 0; /* 选择晶振频率 */
	CAN0CTL1_LOOPB = 0; 
	CAN0CTL1_LISTEN = 0; 
	
  /* 用4M晶振100 kb rate */  
  CAN0BTR0_SJW =1;	  /* SJW=2tq*/
  CAN0BTR0_BRP =1;		/* 分频 2 */
  CAN0BTR1_SAMP =0;		/* one sample per bit */
  CAN0BTR1_TSEG_20 =6;  /* Tseg2=7 */
  CAN0BTR1_TSEG_10 =11; /* Tseg1=12 */
  
  CAN0IDAC  = 0; /* two 32bit acceptance filter*/
  /*下面仅配置为接受ID=02的扩展贞格式,此时Hit 0 命中,但对于ID=0的标准贞也接受,此时Hit 1命中*/
	CAN0IDAR0 =0x00; 
	CAN0IDAR1 =0x00; 
	CAN0IDAR2 =0x00;
	CAN0IDAR3 =0x04; //接受ID=2
	CAN0IDMR0 = 0x00; 
	CAN0IDMR1 =0x18;//屏蔽SRR和IDE
  CAN0IDMR2 = 0x00;
  CAN0IDMR3 = 0x01;//屏蔽RTR
	
	CAN0IDAR4 =0x00;//注意：如果标准贞ID设为1000，则也可接收到，因为1000已超出11位，所以此时的ID也为0
	CAN0IDAR5 =0x00;
	CAN0IDAR6 =0x00;
  CAN0IDAR7 =0x00;	
	CAN0IDMR4 = 0x00;
  CAN0IDMR5 = 0x00;
  CAN0IDMR6 = 0x00;
  CAN0IDMR7 = 0x00;

  CAN0CTL0_INITRQ = 0;
	while(CAN0CTL1_INITAK!=0);
	CAN0RIER_RXFIE = 1;	/* 接收中断使能，禁止发送中断 */
	CAN0TIER = 0;			
}

uchar CAN_Transmit(void)

{
	mask = CAN0TFLG;				 
  CAN0TBSEL= mask;        
  mask = CAN0TBSEL;        
  CAN0TXIDR0  = 0x00;			 
  CAN0TXIDR1  = 0x08;		//扩展桢
  CAN0TXIDR2  = 0x00;
  CAN0TXIDR3  = 0x04; //发送ID=2
  CAN0TXDSR0  = 200;	 
  CAN0TXDSR1  = 212;
  CAN0TXDSR2  = 111;
  CAN0TXDSR3  = 23;
  CAN0TXDSR4  = 89;
  CAN0TXDSR5	= 155;
  CAN0TXDSR6  = 199;
  CAN0TXDSR7  = 0;
  CAN0TXDLR		= 0x08;						 
  CAN0TXTBPR  = 0x00;						
  CAN0TFLG = mask; 
  return mask;								 
}

/* MSCAN 接收中断*/
/*中断入口： VECTOR ADDRESS 0XFFB2 CANReceive_ISR*/
interrupt void CANReceive_ISR(void) {

	if (CAN0RXIDR1_IDE)
   {
   CANReceive[0]=CAN0RXIDR0;		 /* 扩展29位 */
   CANReceive[1]=CAN0RXIDR1;
   CANReceive[2]=CAN0RXIDR2;
   CANReceive[3]=CAN0RXIDR3;
   CANReceive[4]=CAN0RXDLR&0x0F; 
   CANReceive[5]=CAN0RXDSR0;     
   CANReceive[6]=CAN0RXDSR1;     
   CANReceive[7]=CAN0RXDSR2;     
   CANReceive[8]=CAN0RXDSR3;     
   CANReceive[9]=CAN0RXDSR4;     
   CANReceive[10]=CAN0RXDSR5;    
   CANReceive[11]=CAN0RXDSR6;    
   CANReceive[12]=CAN0RXDSR7;    
   }
  else
   {
   CANReceive[0]=CAN0RXIDR0;     /* 标准11位 */
   CANReceive[1]=CAN0RXIDR1;
   CANReceive[2]=CAN0RXDLR&0x0F; 
   CANReceive[3]=CAN0RXDSR0;     
   CANReceive[4]=CAN0RXDSR1;     
   CANReceive[5]=CAN0RXDSR2;     
   CANReceive[6]=CAN0RXDSR3;     
   CANReceive[7]=CAN0RXDSR4;     
   CANReceive[8]=CAN0RXDSR5;     
   CANReceive[9]=CAN0RXDSR6;    
   CANReceive[10]=CAN0RXDSR7;    
   } 
  for(i=0;i<13;i++){
sprintf(buf,"%d\n",CANReceive[i]);TransmitT(buf);}
	CAN0RFLG_RXF=1; 
}