两块 DSP2812 对接 CAN通信

foreverlove3721

两块 DSP2812 对接 CAN通信 [复制链接]

哪位亲做过 两块 DSP2812 对接 CAN通信,一片 做接收,一片做发送file:///C:/DOCUME~1/ADMINI~1/LOCALS~1/Temp/X1%60E@%60R9LLX~6VHSWO%60NXY0.gif   

我目前通信失败,找不出因由,望指教 ,既不发送成功,也不能接收成功


我两片 DSP的ECAN的初始化都是这样的,是个例程里面的, 我对照过TI的文档,初始化的顺序也是对的:


void InitECan(void)
{   
struct ECAN_REGS ECanaShadow;
EALLOW;

//配置GPIO引脚工作在eCAN功能
GpioMuxRegs.GPFMUX.bit.CANRXA_GPIOF7=1;
GpioMuxRegs.GPFMUX.bit.CANTXA_GPIOF6=1;

//配置eCAN的RX和TX分别为eCAN的接收和发送引脚
ECanaShadow.CANTIOC.all = ECanaRegs.CANTIOC.all;
ECanaShadow.CANTIOC.bit.TXFUNC = 1;
ECanaRegs.CANTIOC.all = ECanaShadow.CANTIOC.all;

ECanaShadow.CANRIOC.all = ECanaRegs.CANRIOC.all;
ECanaShadow.CANRIOC.bit.RXFUNC = 1;
ECanaRegs.CANRIOC.all = ECanaShadow.CANRIOC.all;
EDIS;

EALLOW;
ECanaShadow.CANMC.all = ECanaRegs.CANMC.all;
ECanaShadow.CANMC.bit.STM = 0;    //工作在正常模式
ECanaShadow.CANMC.bit.SCM = 1;    //工作在ecan模式
ECanaRegs.CANMC.all = ECanaShadow.CANMC.all;
EDIS;

//初始化所有主设备控制区域为0，MCF所有的位都初始化为0
ECanaMboxes.MBOX0.MCF.all = 0x00000000;
    ECanaMboxes.MBOX1.MCF.all = 0x00000000;
ECanaMboxes.MBOX2.MCF.all = 0x00000000;
ECanaMboxes.MBOX3.MCF.all = 0x00000000;
ECanaMboxes.MBOX4.MCF.all = 0x00000000;
ECanaMboxes.MBOX5.MCF.all = 0x00000000;
ECanaMboxes.MBOX6.MCF.all = 0x00000000;
ECanaMboxes.MBOX7.MCF.all = 0x00000000;
ECanaMboxes.MBOX8.MCF.all = 0x00000000;
ECanaMboxes.MBOX9.MCF.all = 0x00000000;
ECanaMboxes.MBOX10.MCF.all = 0x00000000;
ECanaMboxes.MBOX11.MCF.all = 0x00000000;
ECanaMboxes.MBOX12.MCF.all = 0x00000000;
ECanaMboxes.MBOX13.MCF.all = 0x00000000;
ECanaMboxes.MBOX14.MCF.all = 0x00000000;
ECanaMboxes.MBOX15.MCF.all = 0x00000000;
ECanaMboxes.MBOX16.MCF.all = 0x00000000;
ECanaMboxes.MBOX17.MCF.all = 0x00000000;
ECanaMboxes.MBOX18.MCF.all = 0x00000000;
ECanaMboxes.MBOX19.MCF.all = 0x00000000;
ECanaMboxes.MBOX20.MCF.all = 0x00000000;
ECanaMboxes.MBOX21.MCF.all = 0x00000000;
ECanaMboxes.MBOX22.MCF.all = 0x00000000;
ECanaMboxes.MBOX23.MCF.all = 0x00000000;
ECanaMboxes.MBOX24.MCF.all = 0x00000000;
ECanaMboxes.MBOX25.MCF.all = 0x00000000;
ECanaMboxes.MBOX26.MCF.all = 0x00000000;
ECanaMboxes.MBOX27.MCF.all = 0x00000000;
ECanaMboxes.MBOX28.MCF.all = 0x00000000;
ECanaMboxes.MBOX29.MCF.all = 0x00000000;
ECanaMboxes.MBOX30.MCF.all = 0x00000000;
ECanaMboxes.MBOX31.MCF.all = 0x00000000;
/* Clear all TAn bits */
ECanaRegs.CANTA.all = 0xFFFFFFFF;

/* Clear all RMPn bits */
ECanaRegs.CANRMP.all = 0xFFFFFFFF;

/* Clear all interrupt flag bits */
ECanaRegs.CANGIF0.all = 0xFFFFFFFF;
ECanaRegs.CANGIF1.all = 0xFFFFFFFF;

/* Configure bit timing parameters */
EALLOW;
//ECanaRegs.CANMIM.all = 0xFFFFFFFF;  /*邮箱中断使能*/
ECanaShadow.CANMC.all = ECanaRegs.CANMC.all;
ECanaShadow.CANMC.bit.CCR = 1;
ECanaRegs.CANMC.all = ECanaShadow.CANMC.all;
EDIS;

//CPU请求向CANBTC和CANGAM写配置信息，该位置1后必须等到CANED.CCE为1，才能
//对CANBTC进行操作。
do
{
   ECanaShadow.CANES.all = ECanaRegs.CANES.all;
}while(ECanaShadow.CANES.bit.CCE != 1);

EALLOW;
/*(BRPREG+1)=10 feeds a 15MHz CAN clock*/
ECanaShadow.CANBTC.bit.BRP = 9;
/*150/10=15*/
ECanaShadow.CANBTC.bit.TSEG2 = 2;
ECanaShadow.CANBTC.bit.TSEG1 = 10;
ECanaRegs.CANBTC.all = ECanaShadow.CANBTC.all;

ECanaShadow.CANMC.all = ECanaRegs.CANMC.all;
ECanaShadow.CANMC.bit.CCR = 0;
ECanaRegs.CANMC.all = ECanaShadow.CANMC.all;
EDIS;
do
{
  ECanaShadow.CANES.all = ECanaRegs.CANES.all;
}while(ECanaShadow.CANES.bit.CCE != 0);  //等待CCE位清零

//屏蔽所有邮箱
ECanaRegs.CANME.all = 0;  //在写MSGID之前要完成该操作

/*发送邮箱的ID号*/
ECanaMboxes.MBOX0.MID.all = 0x00C80000;

/*接收邮箱的ID号*/
ECanaMboxes.MBOX16.MID.all =  0x00C80000;

/*邮箱0为TX，16为RX*/
ECanaShadow.CANMD.all = ECanaRegs.CANMD.all;
ECanaShadow.CANMD.bit.MD0 =0;
    ECanaShadow.CANMD.bit.MD16 =1;
ECanaRegs.CANMD.all = ECanaShadow.CANMD.all;


/*数据长度 8个BYTE*/
ECanaMboxes.MBOX0.MCF.bit.DLC = 8;
ECanaMboxes.MBOX16.MCF.bit.DLC = 8;
   
//设置发送优先级  2009.3.15 Add
ECanaMboxes.MBOX0.MCF.bit.TPL = 0;
ECanaMboxes.MBOX16.MCF.bit.TPL = 0;
   
   
/*没有远方应答帧被请求*/
ECanaMboxes.MBOX0.MCF.bit.RTR = 0;
ECanaMboxes.MBOX16.MCF.bit.RTR = 0;


//向邮箱RAM区写数据
ECanaMboxes.MBOX0.MDRL.all = 0x01234567;
ECanaMboxes.MBOX0.MDRH.all = 0x89ABCDEF;
    //邮箱使能Mailbox0

ECanaShadow.CANME.all = ECanaRegs.CANME.all;
ECanaShadow.CANME.bit.ME0 =1;
ECanaShadow.CANME.bit.ME16 =1;
ECanaRegs.CANME.all = ECanaShadow.CANME.all;
}

renton

有没有使用Transceiver啊？如果没有的话，是没法成功的，CAN模块需要通过收发器从总线上把自己发出的bit读取回来做仲裁判断，如果没有用Transceiver，那么TX发送1，RX读取回来是0，CAN模块就认为自己丢失了仲裁权了，所以不能成功。
土办法是把两个片子的TX和RX都连在一起，但是需要引脚能够设置成开漏模式才行，否则两边发送不同电平的时候，引脚就烧了...

foreverlove3721

file:///C:/Documents%20and%20Settings/Administrator/Application%20Data/Tencent/Users/472920150/QQ/WinTemp/RichOle/%60LW07TWV%7B]VYH%257@6R1(%25IY.jpg[img]file:///C:/Documents%20and%20Settings/Administrator/Application%20Data/Tencent/Users/472920150/QQ/WinTemp/RichOle/HF0FPK$%25~2_Y%60[IOUQH)F$N.jpg[/img]
这是两块开发板的CAN通信的驱动芯片,这样接可以正常通信不?

maylove

图片打不开，你下载到本地再上传！

laotouzi112

renton 发表于 2012-12-25 11:21
有没有使用Transceiver啊？如果没有的话，是没法成功的，CAN模块需要通过收发器从总线上把自己发出的bit读 ...

我的开发板上有收发器，还是不行啊！

chjlx2012

您好，楼主，您的问题解决了吗，我这也是遇到了同样的问题，求解，非常感谢