can._c

MCU：ATMEGA8515 Frequence: 16M 描述：利用已有CAN TEST V1.0电路板进行调试, 可靠性测试已通过

/******************************************
MCU：ATMEGA8515
Frequence: 8M
******************************************/
#include "iom8515v.h"
#include "macros.h"
#include "MAIN.h"
#include "CAN.h"
#define startadd 0x7f00		//SJA1000的首地址
uchar CanMode[14];
uchar TransBuffer[13];
uchar RxBuffer[13];
uchar RevFlag;
#define FALSE 0
#define TRUE 1
#define MODE	0x00		//模式寄存器
#define CMR		0x01		//命令寄存器
#define SR		0x02		//状态寄存器
#define IR		0x03		//中断寄存器
#define IER		0x04		//中断使能寄存器
#define BTR0	0x06		//总线时序寄存器0
#define BTR1	0x07		//总线时序寄存器1
#define OCR		0x08		//输出控制寄存器 
#define TEST	0x09
#define ALC		0x0B		//仲裁丢失捕捉寄存器
#define ECC		0x0C		//错误代码捕捉寄存器
#define EWLR	0x0D		//错误报警限额寄存器
#define RXERR	0x0E		//RX错误计数寄存器
#define TXERR	0x0F		//TX错误计数寄存器
#define ACR0	0x10		//验收代码寄存器
#define ACR1	0x11
#define ACR2	0x12
#define ACR3	0x13
#define AMR0	0x14		//验收屏障寄存器
#define AMR1	0x15
#define AMR2	0x16
#define AMR3	0x17
///////////////////////////
#define TXEFF   0x10
#define TXID0   0x11
#define TXID1   0x12
#define TXID2   0x13
#define TXID3   0x14

#define RXEFF   0x10
#define RXID0   0x11
#define RXID1   0x12
#define RXID2   0x13
#define RXID3   0x14

#define TXDATA0 0x15
#define TXDATA1 0x16
#define TXDATA2 0x17
#define TXDATA3 0x18
#define TXDATA4 0x19
#define TXDATA5 0x1A
#define TXDATA6 0x1B
#define TXDATA7 0x1C

#define RXDATA0 0x15
#define RXDATA1 0x16
#define RXDATA2 0x17
#define RXDATA3 0x18
#define RXDATA4 0x19
#define RXDATA5 0x1A
#define RXDATA6 0x1B
#define RXDATA7 0x1C
//////////////////////////
#define RMC		0x1D		//RX报文计数器
#define RBSA	0x1E		//RX缓冲器起始地址寄存器
#define CDR		0x1F		//时钟分频寄存器
//////////////////////////////////////////////////////////////////////
uchar *sja_address=(uchar *)startadd;

uchar read_sja(uchar addr) 				   //读SJA1000状态寄存器子程序
{
	sja_address=(uchar *)startadd;
	sja_address=sja_address+addr;
	return (*(sja_address));
}

void write_sja(uchar addr,uchar val) 	   //写SJA1000控制寄存器子程序
{
	sja_address=(uchar *)startadd;
	sja_address=sja_address+addr;
	*(sja_address)=val;
}

/*************************************************
            初始化SJA1000主控制器子函数
*************************************************/
void Init_CAN(void)                
{
	uchar temp;
	uint k ; 
	CLI();
	write_sja(MODE,0x09);
	read_sja(IR);		 	   	    //读取CAN的中断标识
	while(!(read_sja(MODE)&0x01))	//检测SJA1000是否达到复位工作模式
	{
	   write_sja(MODE,0x01);		//进入复位工作模式
	}
	
	for(k=0;k<6;k++); 				//延时约5us
	write_sja(CDR,0xC8);            //PeliCAN 模式,禁能CLOCKOUT引脚
	for(k=0;k<6;k++); 				//延时约5us
	write_sja(BTR0,0x04); 	        //设置时钟分频器,500k
	write_sja(BTR1,0x1c); 	        
	write_sja(OCR,0x1a); 	        //输出控制
	write_sja(RXERR,0x00);			
	write_sja(TXERR,0x00);
	write_sja(ECC,0x00);
	write_sja(RBSA,0x00);			//缓存器起始地址寄存器设置为0
	
	write_sja(ACR0,0x00); 	        //acceptcode default ffffffff
	write_sja(ACR1,0x00);
	write_sja(ACR2,0x00);
	write_sja(ACR3,0x00);

	write_sja(AMR0,0xff);  			//acceptmask default ffffffff
	write_sja(AMR0,0xff);
	write_sja(AMR0,0xff);
	write_sja(AMR0,0xff);

	write_sja(IER,0x01);            //开放接收中断
	write_sja(CMR,0x0c);		  	//清除数据溢出和释放接收缓冲器;
	do
	{
	   write_sja(MODE,0x08); 		//设置SJA1000 工作模式，单滤波接收工作模式
	}
	while((read_sja(MODE)&0x01));	//确认复位标志是否被删除                      
	SEI();
}

/*************************************************
                SJA1000发送子函数
*************************************************/
void CanTransmit(void) 
{ 
	uchar status;
	CLI();		   	   	 		   //关中断		
	TransBuffer[0]=0x88;		
	TransBuffer[1]=0x00;	
	TransBuffer[2]=0x00;	
	TransBuffer[3]=0x00;	
	TransBuffer[4]=0x00;	
	TransBuffer[5]=0x01;	
	TransBuffer[6]=0x02;	
	TransBuffer[7]=0x03;	
	TransBuffer[8]=0x04;	
	TransBuffer[9]=0x05;	
	TransBuffer[10]=0x06;	
	TransBuffer[11]=0x07;	
	TransBuffer[12]=0xaa;					  
	while(!(read_sja(SR)&0x04));   //wait until reg2^2==1 ,即判断发送缓冲器的状态
	write_sja(TXEFF,TransBuffer[0]);		   //扩展帧，数据长度为8个字节
	write_sja(TXID0,TransBuffer[1]);
	write_sja(TXID1,TransBuffer[2]);
	write_sja(TXID2,TransBuffer[3]);
	write_sja(TXID3,TransBuffer[4]);
	write_sja(TXDATA0,TransBuffer[5]);
	write_sja(TXDATA1,TransBuffer[6]);
	write_sja(TXDATA2,TransBuffer[7]);
	write_sja(TXDATA3,TransBuffer[8]);
	write_sja(TXDATA4,TransBuffer[9]);
	write_sja(TXDATA5,TransBuffer[10]);
	write_sja(TXDATA6,TransBuffer[11]);
	write_sja(TXDATA7,TransBuffer[12]);
	write_sja(CMR,0x01);		  //发送请求命令
	while(!(read_sja(SR) & 0x08));//检测SR.3位，判断发送是否完成
	SEI();				  	  	  //开中断
}
/*
void Search(void)                 //查询方式接收
{
   uchar SearchStatus=read_sja(SR);	//读取状态寄存器
   if(!(SearchStatus & 0xc3))		//是否存在总线关闭、错误状态、数据溢出、有数据位等状态
   {
      if((SearchStatus & 0x80) != 0)//如果总线关闭
	  {
	     read_sja(IR);	            //读取中断寄存器，清除中断位
		 write_sja(MODE,0x08); 
	  }
	  else
	  {
	     read_sja(IR);
         if((read_sja(IR) & 0x08) != 0)//如果有数据溢出
		 write_sja(CMR,0x0c);	       //在命令寄存器中清除数据溢出和释放接收缓冲区
		 else
		 {
		    if((read_sja(IR) & 0x01) != 0)//IR.0=1，接收缓冲区有数据
			{
			    Status_lighting(1);
				RevFlag=1;
		    }
	     }
	  }
   }
}*/


uchar Receive(void)
{
 	uchar result=FALSE;
	uchar status,number,i,sff;
	uchar prbuf;
	uchar RxData[13];
	status=read_sja(SR);
	prbuf=RXEFF;
	if((status&0xc3)!=0)  		  //读取总线脱离、错误状态、接收溢出、有数据等位
	{
		if((status&0x80)==0x80)
		{
			write_sja(MODE,0x00);
			return FALSE;
		}
		if((status&0x02)==0x02)
		{
			write_sja(CMR,0x0c);
			return FALSE;
		}
		
		if((status&0x01)==0x01)
		{
			if((read_sja(RXEFF)&0x40)==0x40)  //如果RTR=1，为远程帧
			{
				write_sja(CMR,0x04);		  //则释放FXFIFO
			}
			else							  //为0，则是数据帧
			{
				sff=read_sja(prbuf)&0x80;	  //取第一个字节的最高位
				number=(read_sja(prbuf)&0x0f);//取第一个字节的低四位，即数据长度
				if ((sff&0x80)==0x80)		  //判断是标准帧还是扩展帧
				number=number+5;			  //扩展帧，则帧的总长度加5(13字节)
				else
				number=number+3;			  //标准帧，则帧的总长度加3(11字节)
				for(i=0;i<number;i++)		  //读取数据
				{
					RxBuffer[i]=read_sja(prbuf);
					prbuf++;
				}
				result=TRUE;	 		 	  //读取到正确的数据则返回TRUE
				write_sja(CMR,0x04);		  //最后释放FXFIFO
			}
		}
	}
	return result;
}