can发送失败

只看该作者 · 2014-2-28 19:55

测试2812片子CAN通信时，用的是从TI网站下的ECAN通信源代码，但无论如何CAN通信都调试不通，查看寄存器的时候是TA无法置1，求助各位了

只看该作者 · 2014-2-28 19:55

#include \"DSP28_Device.h\"
#define TXCOUNT  10000  // Transmission will take place (TXCOUNT) times..

long    i;
long          loopcount = 0;

void InitECan(void);

main()
{

/* Create a shadow register structure for the CAN control registers. This is
needed, since, only 32-bit access is allowed to these registers. 16-bit access
to these registers could potentially corrupt the register contents. This is
especially true while writing to a bit (or group of bits) among bits 16 - 31 */

struct ECAN_REGS ECanaShadow;

/* Initialize the CAN module */

      InitECan();

/* Write to the MSGID field  */

ECanaMboxes.MBOX5.MSGID.all = 0x9FFFFFFF; // Extended Identifier

/* Configure Mailbox under test as a Transmit mailbox */

      ECanaShadow.CANMD.all = ECanaRegs.CANMD.all;
      ECanaShadow.CANMD.bit.MD5 = 0;
      ECanaRegs.CANMD.all = ECanaShadow.CANMD.all;

/* Enable Mailbox under test */

      ECanaShadow.CANME.all = ECanaRegs.CANME.all;
      ECanaShadow.CANME.bit.ME5 = 1;
      ECanaRegs.CANME.all = ECanaShadow.CANME.all;

/* Write to DLC field in Master Control reg */

      ECanaMboxes.MBOX5.MCF.bit.DLC = 8;

/* Write to the mailbox RAM field */

   ECanaMboxes.MBOX5.MDRL.all = 0x01234567;
      ECanaMboxes.MBOX5.MDRH.all = 0x89ABCDEF;

/* Begin transmitting */

// while(1)                                                       // Uncomment this line for infinite transmissions
for(i=0; i < TXCOUNT; i++)                               // Uncomment this line for finite transmissions
{

   ECanaShadow.CANTRS.all = 0;
   ECanaShadow.CANTRS.bit.TRS5 = 1;    // Set TRS for mailbox under test
   ECanaRegs.CANTRS.all = ECanaShadow.CANTRS.all;

   while(ECanaRegs.CANTA.bit.TA5 == 0 ) {}  // Wait for TA5 bit to be set..
//***问题就出在这里，TA5无法置1所以CAN通信怎么也不通*****************
**********************************************************
**********************************************************

   ECanaShadow.CANTA.all = 0;
   ECanaShadow.CANTA.bit.TA5 = 1;             // Clear TA5
   ECanaRegs.CANTA.all = ECanaShadow.CANTA.all;

   loopcount ++;
}

}

恳请各位指教，多谢了啊！！！！！！！

1万 · 2014-2-28 20:11

这个必须两个板子连接起来才能调试的。

只看该作者 · 2014-2-28 20:39

不知道你是在环回模式下测试还是正常工作模式下测试的,如果是环回模式的话,只要发送和接受邮箱的设置一致肯定不会有问题的,如果你是正常模式下测试的话,首先检查你的Can总线信号是不是正常的,总线如果正常,就需要看总线上的另外can节点的邮箱设置和你的设置是不是一样的.
邮箱设置的时候需要注意接受扩展帧还是标准帧,还是两者都接受.仔细检查一下寄存器有没有配对.