NXP ARM处理器CAN总线程序（keil环境）
源代码在线查看： can.c
/*****************************************************************************
* can.c: CAN module API file for NXP LPC23xx/24xx Family Microprocessors
*
* Copyright(C) 2006, NXP Semiconductor
* All rights reserved.
*
* History
* 2006.09.13 ver 1.00 Prelimnary version, first Release
*
*****************************************************************************/
#include "LPC230x.h" /* LPC23xx definitions */
#include "type.h"
#include "irq.h"
#include "can.h"
// Receive Queue: one queue for each CAN port
extern CAN_MSG MsgBuf_RX1, MsgBuf_RX2;
extern volatile DWORD CAN1RxDone, CAN2RxDone;
DWORD CANStatus;
DWORD CAN1RxCount = 0, CAN2RxCount = 0;
DWORD CAN1ErrCount = 0, CAN2ErrCount = 0;
/******************************************************************************
** Function name: CAN_ISR_Rx1
**
** Descriptions: CAN Rx1 interrupt handler
**
** parameters: None
** Returned value: None
**
******************************************************************************/
void CAN_ISR_Rx1( void )
{
DWORD * pDest;
// 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 = 0x04; // release receive buffer
return;
}
/******************************************************************************
** Function name: CAN_ISR_Rx2
**
** Descriptions: CAN Rx2 interrupt handler
**
** parameters: None
** Returned value: None
**
******************************************************************************/
void CAN_ISR_Rx2( void )
{
DWORD *pDest;
// initialize destination pointer
pDest = (DWORD *)&MsgBuf_RX2;
*pDest = CAN2RFS; // Frame
pDest++;
*pDest = CAN2RID; // ID
pDest++;
*pDest = CAN2RDA; // Data A
pDest++;
*pDest = CAN2RDB; // Data B
CAN2RxDone = TRUE;
CAN2CMR = 0x04; // release receive buffer
return;
}
/*****************************************************************************
** Function name: CAN_Handler
**
** Descriptions: CAN interrupt handler
**
** parameters: None
** Returned value: None
**
*****************************************************************************/
void CAN_Handler(void) __irq
{
IENABLE; /* handles nested interrupt */
CANStatus = CAN_RX_SR;
if ( CANStatus & (1 {
CAN1RxCount++;
CAN_ISR_Rx1();
}
if ( CANStatus & (1 {
CAN2RxCount++;
CAN_ISR_Rx2();
}
if ( CAN1GSR & (1 {
/* The error count includes both TX and RX */
CAN1ErrCount = (CAN1GSR >> 16 );
}
if ( CAN2GSR & (1 {
/* The error count includes both TX and RX */
CAN2ErrCount = (CAN2GSR >> 16 );
}
IDISABLE;
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 = CAN2RxDone = FALSE;
PCONP |= (1
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 = 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.
**
******************************************************************************/
void CAN_SetACCF_Lookup( void )
{
DWORD address = 0;
DWORD i;
DWORD ID_high, ID_low;
// Set explicit standard Frame
CAN_SFF_SA = address;
for ( i = 0; i < ACCF_IDEN_NUM; i += 2 )
{
ID_low = (i ID_high = ((i+1) *((volatile DWORD *)(CAN_MEM_BASE + address)) = ID_low | ID_high;
address += 4;
}
// Set group standard Frame
CAN_SFF_GRP_SA = address;
for ( i = 0; i < ACCF_IDEN_NUM; i += 2 )
{
ID_low = (i ID_high = ((i+1) *((volatile DWORD *)(CAN_MEM_BASE + address)) = ID_low | ID_high;
address += 4;
}
// Set explicit extended Frame
CAN_EFF_SA = address;
for ( i = 0; i < ACCF_IDEN_NUM; i++ )
{
ID_low = (i *((volatile DWORD *)(CAN_MEM_BASE + address)) = ID_low;
address += 4;
}
// Set group extended Frame
CAN_EFF_GRP_SA = address;
for ( i = 0; i < ACCF_IDEN_NUM; i++ )
{
ID_low = (i *((volatile DWORD *)(CAN_MEM_BASE + address)) = ID_low;
address += 4;
}
// Set End of Table
CAN_EOT = address;
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 = 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 )
{
CAN1TFI1 = pTxBuf->Frame & 0xC00F0000;
CAN1TID1 = pTxBuf->MsgID;
CAN1TDA1 = pTxBuf->DataA;
CAN1TDB1 = pTxBuf->DataB;
CAN1CMR = 0x21;
return ( TRUE );
}
else if ( CANStatus & 0x00000400 )
{
CAN1TFI2 = pTxBuf->Frame & 0xC00F0000;
CAN1TID2 = pTxBuf->MsgID;
CAN1TDA2 = pTxBuf->DataA;
CAN1TDB2 = pTxBuf->DataB;
CAN1CMR = 0x41;
return ( TRUE );
}
else if ( CANStatus & 0x00040000 )
{
CAN1TFI3 = pTxBuf->Frame & 0xC00F0000;
CAN1TID3 = pTxBuf->MsgID;
CAN1TDA3 = pTxBuf->DataA;
CAN1TDB3 = pTxBuf->DataB;
CAN1CMR = 0x81;
return ( TRUE );
}
else
{
return ( FALSE );
}
}
/******************************************************************************
** End Of File
******************************************************************************/
