S12 CAN的ID识别问题 CAN

qianwei920

CAN的ID过滤是由MSCAN模块硬件实现的吗？也就是说软件上并不需要去比较接收到的数据帧的ID是不是等于本节点的ID。是这样吗？
CANIDAC寄存器中的IDHIT2～0位怎么用,是不是根据设置的滤波方式，由mscan的硬件去判断是否ID命中了？也就是说软件上不需要任何程序关于ID过滤

brucesj

是靠软件的设置来硬件实现的！

qianwei920

软件不就设置一下屏蔽id的那几个字节吗，是否匹配是由硬件比较完成的呀。

yunfeng

请到飞思卡尔网站网站上看这个文档
Application notes
AN2010/D  -  Using The Motorola msCAN Filter Configuration Tool

dreamcatcher

请问msCAN的ID是怎么设置的？怎么得到的？

zhwdy81

d0-d31
d0 RTR位，为0
d19 IDE 1
d20 SRR 1
d27 DP 0
d28 R 0

其他位填入ID

就是行了
比如说
id：18ff0088
填入后变为：c7fe0110

dreamcatcher

28,27,26, 25, 24,23,22, 21,
20,19,18,SSR,IDE,17,16, 15,
14,13,12, 11, 10, 9, 8, 7,
6, 5, 4, 3, 2, 1, 0,RTR
我明白了！！
非常感谢！！
那么IDR和IDAR寄存器的值是不是应该相同呢？

lingxiang

我现在也正在调试CAN,但是老是不通,请问有谁知道CAN的滤波网络到底是怎样工作的啊?
当MCU接收到CAN总线上的数据时,是样识别本地ID的啊?

lingxiang

还有谁能告诉我一下,CAN如果向另一方发送数据时,对方收不到的话,是不是发送方就停止向外发送数据啊,也及CAN总线上无信号产生啊.

dreamcatcher

我觉得当接收到的IDR寄存器的值与设定的IDAR寄存器的值相同的时候，如果对应的屏蔽寄存器没有屏蔽的话，即过滤器命中，也就是接受成功了！

lingxiang

为什么我的MCU中的CAN在自发自收的情况下是可以通信的,但是在加上MC33989后与另外一个CAN模块进行通信时却始终没有任何信号啊?
有谁遇到过这样的情况啊?
请帮小弟一下,我实在是失去信心在调下去了.一点结果都没有.

dreamcatcher

可能是IDR,IDAR,IDMR寄存器的值不合理把？
你试过给IDMR=$FF,全屏蔽掉，可以通信吗？

lingxiang

上面这位仁兄,我现在把程序也发给你,给我看看好吗?
我现在觉得到不是IDR,IDAR,IDMR的问题,到是MC33989之间不能通信啊.
MC33989该如何使用啊?
#include /* for EnableInterrupts macro */
#include /* include peripheral declarations */

//---------------------定义全局变量------------------//

unsigned int SPI_count=0; //SPI 计数器

void CAN_Transmit(void);


//----------------- transmit SPI program ------------------//

void transmit_SPI (unsigned char SPI_data)
{
PTC_PTC2 = 0 ; PTC_PTC2 = 0 ; PTC_PTC2 = 0 ;
PTC_PTC2 = 0 ; PTC_PTC2 = 0 ; PTC_PTC2 = 0 ; //SPI 端口拉低

while(SPSCR_SPTE==0);
SPDR=SPI_data;

PTC_PTC2 = 0 ; PTC_PTC2 = 0 ; PTC_PTC2 = 0 ;
PTC_PTC2 = 0 ; PTC_PTC2 = 0 ; PTC_PTC2 = 0 ; //SPI 继续端口拉低

PTC_PTC2 = 1 ; PTC_PTC2 = 1 ; // SPI 端口拉高

}




//------------------display function---------------------//
void delay(void) {
int i ;

for( i = 0; i < 100; i++) {


}
}


//------------------timer interrupt program------------------------//

interrupt 4 void TimerInterrupt(void)
{
PSC_PSTOP = 0x01;
PSC_POF = 0x00;
PSC_PRST = 0x01; //clear PSC_POF and let timer modul execute again


__RESET_WATCHDOG(); // kicks the watchdog


SPI_count++;

if(SPI_count==5) //every 100ms SPI W/D
{
transmit_SPI(0xB3);

SPI_count = 0;

CAN_Transmit();

}



PSC_PSTOP = 0;

}


interrupt 17 void CAN_Receive(void) {
unsigned char receive[8]={0,0,0,0,0,0,0,0};
unsigned char id[4] = {0,0,0,0};
PTA_PTA7 = 1;
delay();
PTA_PTA7 = 0;
delay();
id[0] = REC_IDR0;
id[1] = REC_IDR1;
id[2] = REC_IDR2;
id[3] = REC_IDR3;

receive[0] = REC_DSR0;
receive[1] = REC_DSR1;
receive[2] = REC_DSR2;
receive[3] = REC_DSR3;
receive[4] = REC_DSR4;
receive[5] = REC_DSR5;
receive[6] = REC_DSR6;
receive[7] = REC_DSR7;
CRFLG_RXF = 1;


}
//--------------------------- CAN transmit program ----------------------//

void CAN_Transmit(void){

unsigned char emptytest;
unsigned char emptytest0;
unsigned char emptytest1;
unsigned char emptytest2;

emptytest = CTFLG;

emptytest0 = emptytest&0x01; //判断接受区为空
emptytest1 = emptytest&0x02;
emptytest2 = emptytest&0x04;



if(emptytest0!=0)
{
DLR0 = 0x08;


DSR00 = 0xff;
DSR10 = 0x00;
DSR20 = 0xff;
DSR30 = 0x00;
DSR40 = 0xff;
DSR50 = 0x00;
DSR60 = 0xff;
DSR70 = 0x00;


IDR00 = 0x33; // DP256:0x11; AZ60:0x33; GZ16:0x22; MPC555:0x44
IDR10 = 0xFF;
IDR20 = 0xFF;
IDR30 = 0xFE; //extended identifers

TBPR0 = 0x01;

CTFLG = 0x01; //buffer0 启动发送


}



else if(emptytest1!=0)
{
DLR1 = 0x08;


DSR01 = 0xff;
DSR11 = 0x00;
DSR21 = 0xff;
DSR31 = 0x00;
DSR41 = 0xff;
DSR51 = 0x00;
DSR61 = 0xff;
DSR71 = 0x00;

IDR01 = 0x33; // DP256:0x11; AZ60:0x33; GZ16:0x22; MPC555:0x44
IDR11 = 0xFF;
IDR21 = 0xFF;
IDR31 = 0xFE; //extended identifers

TBPR1 = 0x01;

CTFLG = 0x02; //buffer1 启动发送


}




else if(emptytest2!=0)
{
DLR2 = 0x08;


DSR02 = 0xff;
DSR12 = 0x00;
DSR22 = 0xff;
DSR32 = 0x00;
DSR42 = 0xff;
DSR52 = 0x00;
DSR62 = 0xff;
DSR72 = 0x00;

IDR02 = 0x33; // DP256:0x11; AZ60:0x33; GZ16:0x22; MPC555:0x44
IDR12 = 0xFF;
IDR22 = 0xFF;
IDR32 = 0xFE; //extended identifers

TBPR2 = 0x01;

CTFLG = 0x04; //buffer2 启动发送


}


}





//------------------------ Ports initial ------------------------------//
void Init_PORT(void){
DDRA_DDRA7 = 1;

DDRC_DDRC2 = 1; //MC33989 CSB choice
DDRC_DDRC4 = 1;
DDRC_DDRC5 = 1;


DDRE_DDRE4 = 0x0; //PTE4==high, AZ32A als master wird

PTA_PTA7 = 0;
PTC_PTC2 = 1 ;
PTC_PTC4 = 0 ;
PTC_PTC5 = 0 ;

}


//-------------------------SPI initial program-------------------------//

void Init_SPI(void){

SPCR_SPE =1; //设置SPI寄存器
SPCR_SPMSTR = 1;

SPSCR_SPR0=0;
SPSCR_SPR1=0; //bund rate =500k ,CGMOUT=2M hz ,intenal bus clock =1M hz

PTC_PTC2 = 1 ;

}


//--------------------------MSCAN initial program-----------------------//

void Init_MSCAN08(void){

CMCR0 = 0x01; //CAN模块为软复位状态
CMCR1 = 0x04;
CBTR0 = 0x43;
CBTR1 = 0xA3; //波特率为62.5K


CIDAC = 0x00; //接收滤波为32位滤波


CIDAR0 = 0x00; //滤波使它接收一帧
CIDAR1 = 0x00;
CIDAR2 = 0x00;
CIDAR3 = 0x00; //extended identifers

CIDMR0 = 0xFF;
CIDMR1 = 0xFF;
CIDMR2 = 0xFF;
CIDMR3 = 0xFF; //extended identifers



CMCR0 = 0x00; //把CAN模块设置为数据输入输出状态

CRIER = 0xff; //CAN接收中断使能

}





//------------------------MCU initial program------------------------//

void Init_AZ32A(void)
{

//CONFIG1 = 0x70; //cop module enable
//CONFIG2 = 0x09; //配置寄存器初始化,外接晶振4MHZ，内部总线1MHZ
//MORA_COPD = 0x70;

PSC_PPS = 0; //1分频
PSC_POIE = 1; //PIT interrupt enable

PMODH = 0x03;
PMODL = 0xe8; //定时器设置成为1ms产生一次中断

PSC_PSTOP = 0; //PIT 计数器启动

Init_PORT();
Init_MSCAN08(); //MSCAN initial
Init_SPI(); //SPI initial


}

//----------------------------main function----------------------------//

void main(void){

EnableInterrupts; //中断使能

Init_AZ32A(); //调用单片机初始化子程序

//set MC33989 status by SPI
transmit_SPI(0xB3); //set MC33889 watchdog works at no window mode and 350ms
transmit_SPI(0x11); //set MC33889 MCR Reg,and MC33889 works at Normal status
transmit_SPI(0x50); //set MC33889 CAN Reg,and CAN works normal status

for(;;){
/*delay();
transmit_SPI(0xB3);
delay();
CAN_Transmit(); */

//__RESET_WATCHDOG(); /* feeds the dog */
}
}


如果是自发自收,我通过单步调试是可以通信的.也就是我发送成功,接收缓冲寄存器也相应地正确地接收到发送的值.

可是我用2块板子之间进行调试时始终看不到总线上有信号.

请哪位高手帮忙看一下我的程序代码有何问题?

在此谢过!

lingxiang

我始终努力地坚持着,一定要把它调通,这就是我们这个行业的敬业精神!

yanjihu

简单的很，只要打通V2即可，你对手册没有看透