can.c

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/*****************************************************************************
 *  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 <target.h>
#include <can.h>


// Receive Queue: one queue for each CAN port
extern CAN_MSG MsgBuf_RX1, MsgBuf_RX2;
extern volatile uint32_t CAN1RxDone, CAN2RxDone;
struct PASSTHRU_MSG passthru_msg;

uint32_t CANStatus;

CAN_MSG First_Frame_buff[4];
uint8_t First_Frame_insert_idx,First_Frame_extract_idx;
uint8_t First_Keep = 0;

CAN_MSG can1_rx_buff[64];

uint16_t can1_rx_insert_idx, can1_rx_extract_idx;
uint32_t CAN1RxCount = 0, CAN2RxCount = 0;
uint32_t CAN1ErrCount = 0, CAN2ErrCount = 0;

extern uint32_t EXT_ID[2];


volatile uint8_t CAN1RX_ID = 0;

/******************************************************************************
** Function name:		CAN_ISR_Rx1
**
** Descriptions:		CAN Rx1 interrupt handler
**
** parameters:			None
** Returned value:		None
** 
******************************************************************************/
void CAN_ISR_Rx1( void )
{
	
	uint32_t * pDest;

	// initialize destination pointer
	pDest = (uint32_t *)&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
	CAN1RX_ID = 1;
	return;

}

/******************************************************************************
** Function name:		CAN_ISR_Rx2
**
** Descriptions:		CAN Rx2 interrupt handler
**
** parameters:			None
** Returned value:		None
** 
******************************************************************************/
void CAN_ISR_Rx2( void )
{
	uint32_t *pDest;
	uint32_t temp;
	uint32_t Frame_Type;
	
	RX_LED_ON;
	
	temp = CAN2RDA;
	
	
	
	Frame_Type = (temp>> 4) & 0x0000000f;
	
	if(Frame_Type == 1)	//First Frame
	{
		if(!First_Keep)
		{
			
			temp = (can1_rx_insert_idx + 1) % 64;
			can1_rx_buff[can1_rx_insert_idx].Frame = CAN2RFS;
			can1_rx_buff[can1_rx_insert_idx].MsgID = CAN2RID;
			can1_rx_buff[can1_rx_insert_idx].DataA = CAN2RDA;
			can1_rx_buff[can1_rx_insert_idx].DataB = CAN2RDB;
			if(temp != can1_rx_extract_idx)
				can1_rx_insert_idx = temp;
			First_Keep = 1;
			passthru_msg_index = 0;
		}
		else
		{
			temp = (First_Frame_insert_idx + 1) % 4;
			First_Frame_buff[First_Frame_insert_idx].Frame = CAN2RFS;
			First_Frame_buff[First_Frame_insert_idx].MsgID = CAN2RID;
			First_Frame_buff[First_Frame_insert_idx].DataA = CAN2RDA;
			First_Frame_buff[First_Frame_insert_idx].DataB = CAN2RDB;
			if(temp != First_Frame_extract_idx)
				First_Frame_insert_idx = temp;	
		}	
	}
//	else if(Frame_Type == 2)
//	{
//		passthru_msg_data[passthru_msg_index++] = CAN2RDA;
//		passthru_msg_data[passthru_msg_index++] = CAN2RDB;
//		passthru_fc_cnt --;
//	}
	else
	{
		temp = (can1_rx_insert_idx + 1) % 64;
	
			can1_rx_buff[can1_rx_insert_idx].Frame = CAN2RFS;
			can1_rx_buff[can1_rx_insert_idx].MsgID = CAN2RID;
			can1_rx_buff[can1_rx_insert_idx].DataA = CAN2RDA;
			can1_rx_buff[can1_rx_insert_idx].DataB = CAN2RDB;
	
		if(temp != can1_rx_extract_idx)
			can1_rx_insert_idx = temp;
	}
		

/*	pDest = (uint32_t *)&MsgBuf_RX2;
	*pDest = CAN2RFS;  // Frame
	
	pDest++;
	*pDest = CAN2RID; // ID

	pDest++;
	*pDest = CAN2RDA; // Data A
	*pDest = Reverse(*pDest);
	pDest++;
	*pDest = CAN2RDB; // Data B
	*pDest = Reverse(*pDest);
*/

	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) 
{		
  // perform proper ISR entry so thumb-interwork works properly
  ISR_ENTRY();

	CANStatus = CAN_RX_SR;
	if ( CANStatus & (1 << 8) )
	{
		CAN1RxCount++;
		CAN_ISR_Rx1();
	}
	if ( CANStatus & (1 << 9) )
	{
		CAN2RxCount++;
		CAN_ISR_Rx2();
	}
	if ( CAN1GSR & (1 << 6 ) )
	{
		/* The error count includes both TX and RX */
		CAN1ErrCount = (CAN1GSR >> 16 );
	}
	if ( CAN2GSR & (1 << 6 ) )
	{
		/* The error count includes both TX and RX */
		CAN2ErrCount = (CAN2GSR >> 16 );
	}

    VICVectAddr = 0;		/* Acknowledge Interrupt */
  ISR_EXIT();                           // recover registers and return
	return;
}

/******************************************************************************
** Function name:		CAN_Init
**
** Descriptions:		Initialize CAN, install CAN interrupt handler
**
** parameters:			bitrate
** Returned value:		true or false, false if initialization failed.
** 
******************************************************************************/
uint32_t CAN_Init( uint32_t can_btr )
{
	CAN1RxDone = CAN2RxDone = FALSE;
	
	can1_rx_extract_idx = can1_rx_insert_idx = 0;
	

	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 = 0x04;	// CAN in normal operation mode

	// Install CAN interrupt handler
	install_irq( 23, (void *)CAN_Handler, 4 );
//	CAN1IER = CAN2IER = 0x01;		// Enable receive interrupts
	CAN1IER = 0x01;		// Enable receive interrupts
	CAN_SetACCF( ACCF_BYPASS );
	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 )
{
	uint32_t address = 0;
	uint32_t i;
	uint32_t ID_high, ID_low;

	// Set explicit standard Frame  
	CAN_SFF_SA = address;
	for ( i = 0; i < ACCF_IDEN_NUM; i += 1 )
	{
		ID_low = (i << 29) | (EXP_STD_ID << 16);
		ID_high = ((i) << 13) | (EXP_STD_ID << 0);
		*((volatile uint32_t *)(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 += 1 )
	{
		ID_low = (i << 29) | (GRP_STD_ID_LOW << 16);
		ID_high = ((i) << 13) | (GRP_STD_ID_HIGH << 0);
		*((volatile uint32_t *)(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 << 29) | (EXP_EXT_ID << 0);
		*((volatile uint32_t *)(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 << 29) | (EXT_ID[0] << 0);
//		*((volatile uint32_t *)(CAN_MEM_BASE + address)) = ID_low;
//		address += 4; 
//		ID_high = (i << 29) | (EXT_ID[1] << 0);
//		*((volatile uint32_t *)(CAN_MEM_BASE + address)) = ID_high;
//		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( uint32_t 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.
** 
******************************************************************************/
uint32_t CAN1_SendMessage( CAN_MSG *pTxBuf )
{
//    uint32_t 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 );
	}
}

/******************************************************************************
** Function name:		CAN2_SendMessage
**
** Descriptions:		Send message block to CAN2	
**
** 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.
** 
******************************************************************************/
uint32_t CAN2_SendMessage( CAN_MSG *pTxBuf )
{
//    uint32_t CANStatus;
	CANStatus = CAN2SR;
	if ( CANStatus & 0x00000004 )
	{
		CAN2TFI1 = pTxBuf->Frame & 0xC00F0000;
		CAN2TID1 = pTxBuf->MsgID;
		CAN2TDA1 = pTxBuf->DataA;
		CAN2TDB1 = pTxBuf->DataB;
		CAN2CMR = 0x21;
		return ( TRUE );
	}
	else if ( CANStatus & 0x00000400 )
	{
		CAN2TFI2 = pTxBuf->Frame & 0xC00F0000;
		CAN2TID2 = pTxBuf->MsgID;
		CAN2TDA2 = pTxBuf->DataA;
		CAN2TDB2 = pTxBuf->DataB;
		CAN2CMR = 0x41;
		return ( TRUE );
	}
	else if ( CANStatus & 0x00040000 )
	{	
		CAN2TFI3 = pTxBuf->Frame & 0xC00F0000;
		CAN2TID3 = pTxBuf->MsgID;
		CAN2TDA3 = pTxBuf->DataA;
		CAN2TDB3 = pTxBuf->DataB;
		CAN2CMR = 0x81;
		return ( TRUE );
	}
	else
	{
		return ( FALSE );
	}
}

CAN_MSG * CAN1Getch(void)
{
  CAN_MSG * ch;
	
  if (can1_rx_insert_idx == can1_rx_extract_idx) // check if character is available
    return 0;

  ch = &can1_rx_buff[can1_rx_extract_idx++]; // get character, bump pointer
  can1_rx_extract_idx %= 64; // limit the pointer
 
  return ch;
}


CAN_MSG * CAN1GetFirstch(void)
{
  CAN_MSG * ch;
	
  if (First_Frame_insert_idx == First_Frame_extract_idx) // check if character is available
    return 0;

  ch = &First_Frame_buff[First_Frame_extract_idx++]; // get character, bump pointer
  First_Frame_extract_idx %= 4; // limit the pointer
 
  return ch;
}


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