testcan.c

AT90CAN128的CAN功能的测试程序,GCC编译,非常适用

#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>

unsigned char can_transdata[8]={1,2,3,4,5,6,7,8};
unsigned char can_receivedata[8]={8,7,6,5,4,3,2,1};
unsigned char CanReceiveEndFlag;
void InitCAN(void)
{
// CAN控制器 0# 中断接收 ，1#信箱发送数据 
  CANGCON |= (1<<SWRES);                                                        //CAN控制器软复位 
  CANBT1 = 0x0a;                                                                //设置波特率分频因子16MHz,16TQ,250k,=4=3+1,3 
  CANBT2 = 0x0c;                                                                //同步段为1“0x0n”传播段=7=6+1 
  CANBT3 = 0x37;                                                                //相位缓冲PH2=4=3+1，PH1=4=3+1 
  CANTCON = 0xff; 
//--------------can_MOB INITIAL------------------- 
//MOB0=RX[CMD]    接收上位机发来的指令       
  CANPAGE  = 0x00;                                                              //MOB0,自动增量，初值为0 
  CANSTMOB = 0; 
  CANCDMOB = 0x18;                                                              //can2B,DLC=8 
  CANIDT4 = 0x30;                                                               // 00001 0xx 
  CANIDT3 = 0x00;                                                               // 01111 001              33 
  CANIDT2 = 0x41;                                                               // 10001 111             239 
  CANIDT1 = 0x00;                                                              // 01100 101             177 
  CANIDM4  = 0x00;                                                              //                             11111 100 
  CANIDM3  = 0x00;                                                              //                             11111 111 
  CANIDM2  = 0x00;                                                              //                             11111 111 
  CANIDM1  = 0x00; 
                                                               //CANIDM4-1数据校验屏蔽寄存器  00000 111 
  //MOB1=TX[STA1]  向上位机报告状态组1          6,0,0,178,239,33 
  CANPAGE = 0x10; 
  CANSTMOB = (1<<TXOK); 
  CANCDMOB = 0x18; 
  CANIDT4 = 0x30;                                                               // 00001 000 
  CANIDT3 = 0x80;                                                               // 01111 001              33 
  CANIDT2 = 0x00;                                                               // 10010 111             239 
  CANIDT1 = 0x20;                                                               // 11000 101             178 
                                                           
  CANGIE |= ((1<<ENIT) + (1<<ENRX));                                            //开全局中断 和 接收中断 
  CANIE2 |= 0x09;                                                               //开MOB3 & MOB0信箱接收中断(接收邮箱) 
  CANPAGE  = 0x00; 
  CANCDMOB |= 0x80;                                                             //MOB0接收使能                                                              //MOB3接收使能 
  CANGCON |= 0x02;                                                              //CAN控制器启动 
}
//中断函数     接收CAN数据帧 并 存入数据单元组 
//********************************************************** 
SIGNAL( CANIT_vect ) 
{ 
    unsigned char num_i;
    CANGIE &= ~(1<<ENRX);                  //关接收中断**** 
    CANPAGE = 0x00;                        //
    for(num_i = 0; num_i < 8; num_i++) 
    { 
      can_receivedata[num_i]=CANMSG;           //取得8个字节的数据 
    } 
 
    CANPAGE = 0x00; 
    CANSTMOB &= ~(1<<RXOK);                //清中断标志**** 
    CANCDMOB = 0x98;                       //接收使能 
                         //接收使能 
    CANGIE |= (1<<ENRX);                   //开中断 
    CanReceiveEndFlag=1;
} 
//CAN数据帧发送 

void MOB_send (void) 
{ 
 // CANGIE &= ~(1<<ENRX); 
  unsigned int i; 

  CANPAGE = 0x10;                        //MOB1, auto increment, index 0 
  if (CANSTMOB & (1<<TXOK)) 
  { 
 // CANCDMOB= 0x18; 
  CANSTMOB &= ~(1<<TXOK); 
  for(i = 0; i < 8; i++)
  {
   CANMSG = can_transdata[i]; 
  }
  CANCDMOB = 0x58;                               //帧发送 
  CANGIE |=(1<<ENRX); 
  } 
} 

int main( void )
{
	InitCAN();
	PORTD	= 0xff;
	DDRD	= 0xa9;
//	MOB_send();
	sei();
	CANGIE |= 1<<ENRX;
	while(1)
	{
	 //if(CanReceiveEndFlag==1)
	 {
	    _delay_ms(1);
             MOB_send(); 
             CanReceiveEndFlag=0;
        }
     }
}