PIC18F46K80 CAN环回自测试模式

#include <p18cxxx.h>

/************************************************************/

// CONFIG1L

#pragma config RETEN = OFF      // VREG Sleep Enable bit (Ultra low-power regulator is Disabled (Controlled by REGSLP bit))

#pragma config INTOSCSEL = HIGH // LF-INTOSC Low-power Enable bit (LF-INTOSC in High-power mode during Sleep)

#pragma config SOSCSEL = HIGH   // SOSC Power Selection and mode Configuration bits (High Power SOSC circuit selected)

#pragma config XINST = OFF      // Extended Instruction Set (Disabled)



// CONFIG1H

#pragma config FOSC = INTIO2    // Oscillator (Internal RC oscillator)

#pragma config PLLCFG = OFF     // PLL x4 Enable bit (Disabled)

#pragma config FCMEN = OFF      // Fail-Safe Clock Monitor (Disabled)

#pragma config IESO = OFF       // Internal External Oscillator Switch Over Mode (Disabled)



// CONFIG2L

#pragma config PWRTEN = OFF     // Power Up Timer (Disabled)

#pragma config BOREN = SBORDIS  // Brown Out Detect (Enabled in hardware, SBOREN disabled)

#pragma config BORV = 3         // Brown-out Reset Voltage bits (1.8V)

#pragma config BORPWR = ZPBORMV // BORMV Power level (ZPBORMV instead of BORMV is selected)



// CONFIG2H

#pragma config WDTEN = SWDTDIS  // Watchdog Timer (WDT enabled in hardware; SWDTEN bit disabled)

#pragma config WDTPS = 1048576  // Watchdog Postscaler (1:1048576)



// CONFIG3H

#pragma config CANMX = PORTB    // ECAN Mux bit (ECAN TX and RX pins are located on RB2 and RB3, respectively)

#pragma config MSSPMSK = MSK7   // MSSP address masking (7 Bit address masking mode)

#pragma config MCLRE = ON       // Master Clear Enable (MCLR Enabled, RE3 Disabled)



// CONFIG4L

#pragma config STVREN = ON      // Stack Overflow Reset (Enabled)

#pragma config BBSIZ = BB2K     // Boot Block Size (2K word Boot Block size)



// CONFIG5L

#pragma config CP0 = OFF        // Code Protect 00800-03FFF (Disabled)

#pragma config CP1 = OFF        // Code Protect 04000-07FFF (Disabled)

#pragma config CP2 = OFF        // Code Protect 08000-0BFFF (Disabled)

#pragma config CP3 = OFF        // Code Protect 0C000-0FFFF (Disabled)



// CONFIG5H

#pragma config CPB = OFF        // Code Protect Boot (Disabled)

#pragma config CPD = OFF        // Data EE Read Protect (Disabled)



// CONFIG6L

#pragma config WRT0 = OFF       // Table Write Protect 00800-03FFF (Disabled)

#pragma config WRT1 = OFF       // Table Write Protect 04000-07FFF (Disabled)

#pragma config WRT2 = OFF       // Table Write Protect 08000-0BFFF (Disabled)

#pragma config WRT3 = OFF       // Table Write Protect 0C000-0FFFF (Disabled)



// CONFIG6H

#pragma config WRTC = OFF       // Config. Write Protect (Disabled)

#pragma config WRTB = OFF       // Table Write Protect Boot (Disabled)

#pragma config WRTD = OFF       // Data EE Write Protect (Disabled)



// CONFIG7L

#pragma config EBTR0 = OFF      // Table Read Protect 00800-03FFF (Disabled)

#pragma config EBTR1 = OFF      // Table Read Protect 04000-07FFF (Disabled)

#pragma config EBTR2 = OFF      // Table Read Protect 08000-0BFFF (Disabled)

#pragma config EBTR3 = OFF      // Table Read Protect 0C000-0FFFF (Disabled)



// CONFIG7H

#pragma config EBTRB = OFF      // Table Read Protect Boot (Disabled)

/**************************************************************************8*/





int CAN_FLAG;

//unsigned int CAN_Delay_count=0;

char CAN_Adress_H,CAN_Adress_L;

void initcan()

{

 TRISB=(TRISB|0X08)&0XeB; //设置CANRX/RB3为输入，CANTX/RB2为输出

//设置CAN的波特率为250K，在Fosc=8M时，Tbit=8us，假设BRP=01h

//则TQ=[2*（1+BRP）]/Fosc=2*（1+1）/4=1us。

//NOMINAL BIT RATE=8TQ，SJW=1，Sync_Seg=1TQ,Prog _Seg=1TQ,Phase_Seg1=3TQ,Phase_Seg2=3TQ

CANCON=0X80; //请求进入CAN配置模式REQOP=100

while(CANSTAT&0X80==0){;} //等待进入CAN配置模式OPMODE=100

BRGCON1=0X01; //设置SJW和BRP，SJW=1TQ，BRP=01H

BRGCON2=0X90; //设置Phase_Seg1=3TQ和Prog _Seg=1TQ

BRGCON3=0X42; //设置Phase_Seg2=3TQ

//设置发送邮箱0标识符号和发送的数据

TXB0CON=0X03; //发送优先级为最高优先级，TXPRI=11

TXB0SIDH=CAN_Adress_H; //设置发送缓冲器0的标准标识符，本程序采用标准识符

TXB0SIDL=CAN_Adress_L&0XE0;

TXB0DLC=0X08; //设置数据长度为8个字节

TXB0D0=0X00; //写发送缓冲器数据区的数据

TXB0D1=0X01;

TXB0D2=0X02;

TXB0D3=0X03;

TXB0D4=0X04;

TXB0D5=0X05;

TXB0D6=0X06;

TXB0D7=0X07;

//设置接收邮箱0的标识符和初始化数据

RXB0SIDH=CAN_Adress_H; //设置接收缓冲器0的标识符

RXB0SIDL=CAN_Adress_L&0XE0;

RXB0CON=0X20; //仅仅接收标准标识符的有效信息，FILHIT0=0表示RXB0采用filter0

RXB0DLC=0X08; //设置接收缓冲器0的数据区长度

RXB0D0=0X00; //初始化接收缓冲器0的数据区数据

RXB0D1=0X00;

RXB0D2=0X00;

RXB0D3=0X00;

RXB0D4=0X00;

RXB0D5=0X00;

RXB0D6=0X00;

RXB0D7=0X00;

//初始化接收滤波器0和接收屏蔽，

RXF0SIDH=CAN_Adress_H;

RXF0SIDL=CAN_Adress_L;

RXM0SIDH=0XFF;

RXM0SIDL=0XE0;



//初始化CAN模块的I/O控制寄存器

//CIOCON=0X00;

//CIOCONbits.CLKSEL = 1;

//使CAN进入某种工作模式模式

CANCON=0X40; //=0X40,进入自测试模式;=0x00,正常操作模式

//while(CANSTAT_0&0XE0!=0){;}

while(CANSTAT&0X40==0){;}

//初始化CAN的中断

PIR5=0X00; //清所有中断标志

PIE5=PIE5|0X01; //使能接收缓冲器0的接收中断

IPR5=IPR5|0X01; //接收缓冲器0的接收中断为最高优先级

;

}

#pragma interrupt can_isr 

#pragma code high_ISR=0x08

void high_ISR()

{

 _asm

 goto can_isr 

 _endasm

}

#pragma code

void can_isr()

{

   CAN_FLAG=1;

 PIR5bits.RXB0IF=0;

 RXB0CONbits.RXFUL=0;

}

void delay()

{

int i,j;

for(i=0;i<500;i++)

for(j=0;j<100;j++)

{;}

}

void main()

{

  CAN_Adress_H=0X33;

 CAN_Adress_L=0XE0;

 INTCON=0x00; //禁止所有中断

 CAN_FLAG=0;

 initcan();

 RCONbits.IPEN=1;

 WDTCON=0; //=1,看门狗使能;=0,禁止看门狗

 INTCON=INTCON|0xc0; //使能中断

 while(1)

 {

    if(CAN_FLAG==1)

 {

 CAN_FLAG=0; //清接收到标志

  TXB0CONbits.TXREQ=0; //禁止发送

 TXB0D0=RXB0D0+1; //用接收数据加1来更新发送数据

 TXB0D1=RXB0D1+1;

 TXB0D2=RXB0D2+1;

 TXB0D3=RXB0D3+1;

 TXB0D4=RXB0D4+1;

 TXB0D5=RXB0D5+1;

 TXB0D6=RXB0D6+1;

 TXB0D7=RXB0D7+1;

 }

 else

 {

 TXB0CON=TXB0CON|0X08;

 while( TXB0CONbits.TXREQ){;} //等待发送完成

// while(!TXB0IF) {;}

 //PORTB&=0xEF;

 }

}

}