LPC2378的CAN接口求助

只看该作者 · 2009-10-31 14:40

本帖最后由 mildlioncn 于 2009-11-1 09:22 编辑

驱动器用的是TJA1050，做了两块板子，进行CAN总线通讯实验。一发一收正常，速率大约为100K，并且启动了滤波器。但是我改了两个都发送，并且都可以接收对方的数据，就不能正常工作了。好像收不到数据了。估计可能总线竞争吧。在论坛里找了半天看有无解决办法，好像有一篇和我的类似，但没有给出解决方法。论坛里都说可能是应用层的问题，但在应用上应注意什么问题呢？？？？
波特率肯定没有问题的，否则没有办法一发一收。
通信距离近得很，可以不计。
100K也不算太快。
接收采用的中断方法，在ISR里也仅仅是把数据放在缓冲区里，没有做别的事情。
发送采用查询的方式。
标准帧的格式。一个为0x100，另一个0x110。
我想有没有可能是因为总线竞争导致总线关闭，CAN控制器**了？？？
就是不知道在应用层里有些什么设置可以解决总线竞争的问题。
谢谢了。

只看该作者 · 2009-11-1 09:24

我已经部分解决问题了。确实是软件上的问题。但是还是会出现错误。
1# mildlioncn

只看该作者 · 2009-11-1 18:49

自己顶一个了。经过一天一夜的奋战，终于初步告捷。采用了FULLCAN的模式。之前没有成功，可能因为中断和中断标志位的问题。还是很感谢论坛里的帖子，让我受益匪浅，任何协议必须吃透，才能解决问题。

只看该作者 · 2009-11-1 18:51

初步成功的代码贴出来和大家分享了：

#include "LPC23xx.h"
#include "type.h"
#include "irq.h"
#include "can.h"
#include "uart.h"

// Receive Queue: one queue for each CAN port
extern CAN_MSG MsgBuf_RX1;
extern volatile DWORD CAN1RxDone;
extern volatile DWORD FullCANRxDone;

DWORD CANStatus;
DWORD CAN1RxCount = 0;
DWORD CAN1ErrCount = 0;

_AF_AUTO_STORE_MSG FullCanAutoMsg;

/******************************************************************************
** Function name: CAN_ISR_Rx1
**
** Descriptions: CAN Rx1 interrupt handler
**
** parameters: None
** Returned value: None
**
******************************************************************************/
void CAN_ISR_Rx1( void )
{
  DWORD * pDest;

  Print_Enter();
  Print_String("The pro has entered the CAN_ISR_Rx1!");

  // initialize destination pointer
  pDest = (DWORD *)&MsgBuf_RX1;
  *pDest = CAN1RFS;  // Frame

  pDest++;
  *pDest = CAN1RID; // ID //change by gongjun

  pDest++;
  *pDest = CAN1RDA; // Data A

  pDest++;
  *pDest = CAN1RDB; // Data B

  CAN1RxDone = TRUE;
  CAN1CMR = CAN1CMR | 0x04; // release receive buffer and reset RI flag
  return;
}

/*****************************************************************************
** Function name: CAN_Handler
**
** Descriptions: CAN interrupt handler
**
** parameters: None
** Returned value: None
**
*****************************************************************************/
void CAN_Handler(void) __irq
{
unsigned int StatInt;
unsigned int StatIntOfFullCAN;
unsigned int dat;
unsigned int *pFrame;
_AF_ATUO_FRMSTAT_MSG * pAutoFrm;

//print the CAN1ICR register
StatInt = CAN1ICR; //when CAN1ICR is read,the relevant bit will be cleared but the RI
Print_Enter();
Print_String("The Pro has entered the CAN_Handler!");
Print_Enter();
PrintLong(StatInt);

//print the CAN_FULLCAN_IC0 register
Print_Enter();
StatIntOfFullCAN = CAN_FULLCAN_IC0;
Print_String("The CAN_FULLCAN_IC0 is : ");
PrintLong(StatIntOfFullCAN);
Print_Enter();

if(StatIntOfFullCAN) //received the FULLCAN Message
{
FullCANRxDone = TRUE;
//the Index is certain to be 2, and it may be modified.
pFrame = (unsigned int *)(0xE0038000+Size_LookUp_Table+2*12);
pAutoFrm = (_AF_ATUO_FRMSTAT_MSG *)(0xE0038000+Size_LookUp_Table+2*12);
//save the Message Frame State
FullCanAutoMsg.FRM.dwValue = *pFrame;
PrintLong(*pFrame); //print the Frame State
pAutoFrm->Bits.SEM = 0; //clear the semaphore
Print_Enter();
pFrame++;
FullCanAutoMsg.DataA = *pFrame; //Get the Data
PrintLong(FullCanAutoMsg.DataA);
Print_Enter();
pFrame++;
FullCanAutoMsg.DataB = *pFrame; //Get the Data
PrintLong(FullCanAutoMsg.DataB);
Print_Enter();
}

if(StatInt)
{
if(StatInt & (1<<0)) //the receive int
{
CAN_ISR_Rx1();
}

if(StatInt & (1<<1)) //the TX1 Interrupt
{
Print_Enter();
Print_String("The TX1 Int has taken place!");
}

if(StatInt & (1<<2)) //the error warning Interrupt
{
Print_Enter();
Print_String("The error warning Int has taken place!");
}

if(StatInt & (1<<3)) //the data overrun Interrupt
{
Print_Enter();
Print_String("The data overrun Int has taken place!");
}

if(StatInt & (1<<4)) //the Wake-Up Interrupt
{
Print_Enter();
Print_String("The Wake-Up Int has taken place!");
}

if(StatInt & (1<<5)) //the error passive Interrupt
{
Print_Enter();
Print_String("The Error Passive Int has taken place!");
}

if(StatInt & (1<<6)) //the Arbitration Lost Interrupt
{
Print_Enter();
Print_String("The Arbitration Lost Int has taken place!");
}

if(StatInt & (1<<7)) //the Bus Error Interrupt
{
Print_Enter();
Print_String("The Bus Error Int has taken place!");
}

if(StatInt & (1<<8)) //the ID Ready Interrupt
{
Print_Enter();
Print_String("The ID Ready Int has taken place!");
}

if(StatInt & (1<<9)) //the TX2 Interrupt
{
Print_Enter();
Print_String("The TX2 Int has taken place!");
}

if(StatInt & (1<<10)) //the TX3 Interrupt
{
Print_Enter();
Print_String("The TX3 Int has taken place!");
}
}

if ( CAN1GSR & (1 << 6 ) )
{
/* The error count includes both TX and RX */
CAN1ErrCount = (CAN1GSR >> 16 );
}

  VICVectAddr = 0; /* Acknowledge Interrupt */
  return;
}

/******************************************************************************
** Function name: CAN_Init
**
** Descriptions: Initialize CAN, install CAN interrupt handler
**
** parameters: bitrate
** Returned value: true or false, false if initialization failed.
**
******************************************************************************/
DWORD CAN_Init( DWORD can_btr )
{
  CAN1RxDone = FALSE;
  FullCANRxDone = FALSE;

  PCONP |= (1 << 13) | (1 << 14); // Enable clock to the peripheral

  PINSEL0 &= ~0x00000F0F;
  PINSEL0 |= 0x0000A05; // port0.0~1, function 0x01, port0.4~5, function 0x10

  CAN1MOD = CAN2MOD = 1; // Reset CAN
  CAN1IER = CAN2IER = 0; // Disable Receive Interrupt
  CAN1GSR = CAN2GSR = 0; // Reset error counter when CANxMOD is in reset

  CAN1BTR = CAN2BTR = can_btr;
  CAN1MOD = CAN2MOD = 0x0; // CAN in normal operation mode

  // Install CAN interrupt handler
  install_irq( 23, (void *)CAN_Handler, HIGHEST_PRIORITY );
  CAN1IER = CAN2IER = EIE | DOIE | WUIE | EPIE | ALIE | BEIE;//0x7FF;//0x01; // Enable receive interrupts
  return( TRUE );
}

/******************************************************************************
** Function name: CAN_SetACCF_Lookup
**
** Descriptions: Initialize CAN, install CAN interrupt handler
**
** parameters: bitrate
**
** Returned value: true or false, false if initialization failed.
**
** Revised: 2009.11.1: add enable-bit of fullcan interrupt
******************************************************************************/
void CAN_SetACCF_Lookup( void )
{
DWORD address = 0;
_AF_SFF_CELL Id_Sff_Set;

   CAN_SFF_SA = Size_LookUp_Table; // Set byte size of fullcan look-up table;

Id_Sff_Set.dwValue = 0;
Id_Sff_Set.Bits.UpID = EXP_STD_ID - 1; //the upper id
Id_Sff_Set.Bits.UpFuE = 1;      //enble fullcan int bit
Id_Sff_Set.Bits.UpCh = 0;

Id_Sff_Set.Bits.LoID = EXP_STD_ID - 2; //the lower id
Id_Sff_Set.Bits.LoFuE = 1;
Id_Sff_Set.Bits.LoCh = 0;

*((volatile DWORD *)(CAN_MEM_BASE + address)) = Id_Sff_Set.dwValue;
address += 4;

Id_Sff_Set.dwValue = 0;
Id_Sff_Set.Bits.UpID = EXP_STD_ID+1; //the upper id
Id_Sff_Set.Bits.UpFuE = 1;      //enble fullcan int bit
Id_Sff_Set.Bits.UpCh = 0;

Id_Sff_Set.Bits.LoID = EXP_STD_ID; //the lower id
Id_Sff_Set.Bits.LoFuE = 1;
Id_Sff_Set.Bits.LoCh = 0;

*((volatile DWORD *)(CAN_MEM_BASE + address)) = Id_Sff_Set.dwValue;
address += 4;

CAN_SFF_GRP_SA = address; // Set group standard Frame
CAN_EFF_SA = address;      // Set explicit extended Frame
CAN_EFF_GRP_SA = address;    // Set group extended Frame
CAN_EOT = address;       // Set End of Table

CAN_FULLCAN_IE = 0x01; // Global Enable-bit of FullCan interrupt

return;
}

/******************************************************************************
** Function name: CAN_SetACCF
**
** Descriptions: Set acceptance filter and SRAM associated with
**
** parameters: ACMF mode
** Returned value: None
**
**
******************************************************************************/
void CAN_SetACCF( DWORD ACCFMode )
{
switch ( ACCFMode )
{
case ACCF_OFF:
   CAN_AFMR = ACCFMode;
   CAN1MOD = CAN2MOD = 1; // Reset CAN
   CAN1IER = CAN2IER = 0; // Disable Receive Interrupt
   CAN1GSR = CAN2GSR = 0; // Reset error counter when CANxMOD is in reset
   break;

case ACCF_BYPASS:
   CAN_AFMR = ACCFMode;
   break;

case ACCF_ON:
case ACCF_FULLCAN:
   CAN_AFMR = ACCF_OFF;
   CAN_SetACCF_Lookup();
   CAN_AFMR = ACCF_FULLCAN;//ACCFMode;
   break;

default:
   break;
}
return;
}

/******************************************************************************
** Function name: CAN1_SendMessage
**
** Descriptions: Send message block to CAN1
**
** parameters: pointer to the CAN message
** Returned value: true or false, if message buffer is available,
** message can be sent successfully, return TRUE,
** otherwise, return FALSE.
**
******************************************************************************/
DWORD CAN1_SendMessage( CAN_MSG *pTxBuf )
{
  DWORD CANStatus;

  CANStatus = CAN1SR;
  if ( CANStatus & 0x00000004 ) //visit TBS1 bit
  {
CAN1TFI1 = pTxBuf->Frame & 0xC00F0000;
CAN1TID1 = pTxBuf->MsgID;
CAN1TDA1 = pTxBuf->DataA;
CAN1TDB1 = pTxBuf->DataB;
CAN1CMR = 0x21; //set TR and STB1 bit
return ( TRUE );
  }
  else if ( CANStatus & 0x00000400 )
  {
CAN1TFI2 = pTxBuf->Frame & 0xC00F0000;
CAN1TID2 = pTxBuf->MsgID;
CAN1TDA2 = pTxBuf->DataA;
CAN1TDB2 = pTxBuf->DataB;
CAN1CMR = 0x41;    //set TR and STB2 bit
return ( TRUE );
  }
  else if ( CANStatus & 0x00040000 )
  {
CAN1TFI3 = pTxBuf->Frame & 0xC00F0000;
CAN1TID3 = pTxBuf->MsgID;
CAN1TDA3 = pTxBuf->DataA;
CAN1TDB3 = pTxBuf->DataB;
CAN1CMR = 0x81;    //set TR and STB3 bit
return ( TRUE );
  }
  return ( FALSE );
}

/******************************************************************************
**                         End Of File
******************************************************************************/

只看该作者 · 2009-11-1 18:54

在中断服务程序里头，我只是简单的打印了一些信号，如果真的出现了这些错误，程序该如何处理呢？重新初始化CAN？还是？

只看该作者 · 2009-11-9 22:09

有没有不用FULLCAN的报文滤波

LPC2378的CAN接口求助

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