/****************************************************************************
【文  件  名  稱】MCP2510.C
【功  能  描  述】MCP2510的demo程序代碼
【程  序  版  本】4.0
【創建人及創建日期】龔俊( gongjun98@sohu.com )//2002年11月19日19:26
【修改人及修改日期】龔俊( gongjun98@sohu.com )//2004-12-8 17:25
****************************************************************************/

//***************************************************************************
#include "AT91RM9200.h"
#include "lib_AT91RM9200.h"
#include "def.h"
#include "console.h"
#include "MCP2510.h"
#include "SPI.h"

//***************************************************************************
#define MCP2510_DEBUG    1

#define MCP2510_CS_H		SPCS1_DS()
#define MCP2510_CS_L		SPCS1_EN()

#define MCP2510_SI_H		DOUT_H()
#define MCP2510_SI_L		DOUT_L()

#define MCP2510_SCK_H		SPCK_H()
#define MCP2510_SCK_L		SPCK_L()

#define MCP2510_SO_GET		DIN_GET()	
#define MCP2510_INT_GET		INT2510_GET()
/********************** MCP2510 Instruction *********************************/
#define DELAY_TIME		80
#define MCP2510INSTR_RESET		0xc0		//復位為缺省狀態，并設定為配置模式
#define MCP2510INSTR_READ		0x03		//從寄存器中讀出數據
#define MCP2510INSTR_WRITE		0x02		//向寄存器寫入數據
#define MCP2510INSTR_RTS		0x80		//啟動一個或多個發送緩沖器的報文發送
#define MCP2510INSTR_RDSTAT		0xa0		//讀取狀態
#define MCP2510INSTR_BITMDFY	0x05		//位修改
//***************************************************************************

/****************************************************************************
【功能說明】SPI接口IO片選初始化
****************************************************************************/
void MCP2510_IO_CS_Init( void ) 
{
	SPI_MCP2510_Init() ;
	MCP2510_SI_L ;		//SI put 0
	MCP2510_SCK_L ;		//SCK put 0
	{ U16 k=0; for( ; k <= DELAY_TIME; k++ ) ;  }  //延時至少300ns
	MCP2510_CS_H ;			// unselect the MCP2510
	{ U16 k=0; for( ; k <= DELAY_TIME; k++ ) ;  }  //延時至少300ns
}

/****************************************************************************
【功能說明】SPI接口讀寫開始，片選有效
****************************************************************************/
void MCP2510_RW_Start( void ) 
{
   MCP2510_SI_L ;		//SI put 0
   MCP2510_SCK_L ;		//SCK put 0
   { U16 k=0; for( ; k <= DELAY_TIME; k++ ) ;  }  //延時至少300ns
   MCP2510_CS_L ;			// Select the MCP2510
   { U16 k=0; for( ; k <= DELAY_TIME; k++ ) ;  }  //延時至少300ns
}

/****************************************************************************
【功能說明】SPI接口寫入數據
****************************************************************************/
void Spi_Write( U8 Data ) 
{
	U8 m ;

	for( m = 0; m < 8; m++ )
	{
		if( (Data&0x80)==0x80 )
			MCP2510_SI_H;		//SI put 1
		else
			MCP2510_SI_L;		//SI put 0

		{ U16 k=0; for( ; k <= DELAY_TIME; k++ ) ;  }  //延時至少300ns
		MCP2510_SCK_H ;		//SCK put 1
		Data = Data<<1 ;
		MCP2510_SCK_L ;		//SCK put 0
		{ U16 k=0; for( ; k <= DELAY_TIME; k++ ) ;  }  //延時至少300ns
	}
}

/****************************************************************************
【功能說明】SPI接口讀出數據
****************************************************************************/
U8 Spi_Read( )
{
	U8 m ;
	U8 data = 0 ;

	for( m = 0; m < 8; m++ )
	{
		MCP2510_SCK_H ;		//SCK put 1
		{ U16 k=0; for( ; k <= DELAY_TIME; k++ ) ;  }  //延時至少300ns
		data = data<<1;
		if( MCP2510_SO_GET != 0 )
			data |= 0x01 ;
		else
			data &= 0xfe;

		{ U16 k=0; for( ; k <= DELAY_TIME; k++ ) ;  }  //延時至少300ns
		MCP2510_SCK_L ;		//SCK put 0
		{ U16 k=0; for( ; k <= DELAY_TIME; k++ ) ;  }  //延時至少300ns
	}

	return (data);
}

/****************************************************************************
【功能說明】 Send Command to MCP2510 via SPI 
****************************************************************************/
void SendCMDMCP2510( U8 CMD )
{
   MCP2510_RW_Start() ;		//Initial IO port and CS is select
   Spi_Write( CMD );
   MCP2510_CS_H ;			// Deselect the MCP2510
}

/****************************************************************************
【功能說明】軟件復位MCP2510
****************************************************************************/
void MCP2510_Reset()
{
	MCP2510_RW_Start() ;
	Spi_Write( MCP2510INSTR_RESET );
	MCP2510_CS_H ;
}

/****************************************************************************
【功能說明】向MCP2510指定地址寫入一個字節
****************************************************************************/
void MCP2510_Write( U8 address, U8 value)
{
	MCP2510_RW_Start() ;

	Spi_Write(MCP2510INSTR_WRITE);
	Spi_Write( address );
	Spi_Write( value );

	MCP2510_CS_H ;
}

/****************************************************************************
【功能說明】修改指定地址寄存器的某些位
****************************************************************************/
void MCP2510_WriteBits( U8 address, U8 data, U8 mask )
{
	MCP2510_RW_Start() ;

	Spi_Write( MCP2510INSTR_BITMDFY );
	Spi_Write( address);
	Spi_Write( mask);
	Spi_Write( data);

	MCP2510_CS_H ;
}

/****************************************************************************
【功能說明】              Read often used status
//Status 	 7    	6    	5    	4    	3    	2  	1	0
//		|	|	|	|	|	|	|	|									
//		|	|	|	|	|	|	|	|___CANINTF.RX0IF
//		|	|	|	|	|	|	|_______CANINTF.RX1IF
//		|	|	|	|	|	|___________TXB0CTRL.TXREQ
//		|	|	|	|	|_______________CANINTF.TX0IF
//		|	|	|	|___________________TXB1CTRL.TXREQ
//		|	|	|_______________________CANINTF.TX1IF
//		|	|___________________________TXB2CTRL.TXREQ
//		|_______________________________CANINTF.TX2IF
****************************************************************************/
unsigned char MCP2510_ReadStatus()
{
	unsigned char result;

	MCP2510_RW_Start() ;

	Spi_Write(MCP2510INSTR_RDSTAT);
	result = Spi_Read() ;
	Spi_Write( 0 ) ;		//數據重復輸出
	MCP2510_CS_H ;

	//if( MCP2510_DEBUG )		printf( "StatusREG = 0x%x\n", result ) ;
	return result;
}

/****************************************************************************
【功能說明】從MCP2510指定地址中讀出一個字節
****************************************************************************/
unsigned char MCP2510_Read( U8 address )
{
	unsigned char result;

	MCP2510_RW_Start() ;

	Spi_Write(MCP2510INSTR_READ) ;		//0x03
	Spi_Write( address ) ;
	result = Spi_Read() ;

	MCP2510_CS_H ;

	return result ;
}

/****************************************************************************
【功能說明】序列讀取MCP2510數據	
****************************************************************************/
void MCP2510_SRead( U8 address, unsigned char* pdata, U8 nlength )
{
	int i;

	MCP2510_RW_Start() ;
	Spi_Write(MCP2510INSTR_READ);
	Spi_Write( address );

	for (i=0; i<nlength; i++)
	{
		*pdata=Spi_Read();
		//if( MCP2510_DEBUG )    printf( "  0x%x\n", (unsigned char)*pdata ) ;
		pdata++;
	}
	MCP2510_CS_H ;
}


/****************************************************************************
【功能說明】序列寫入MCP2510數據	
****************************************************************************/
void MCP2510_Swrite( U8 address, unsigned char* pdata, U8 nlength)
{
	int i;
	MCP2510_RW_Start() ;

	Spi_Write(MCP2510INSTR_WRITE);
	Spi_Write((unsigned char)address);

	for (i=0; i < nlength; i++) 
	{
		Spi_Write( (unsigned char)*pdata );
		//if( MCP2510_DEBUG )    printf( "0x%x\n", (unsigned char)*pdata ) ;
		pdata++;
	}
	MCP2510_CS_H ;
}

/****************************************************************************
【功能說明】
****************************************************************************/
void MCP2510_SetBandRate(CanBandRate bandrate, int IsBackNormal)
{
	U8 value=0;
	U8 ReadBackCNT = 0;

	// Bit rate calculations.
	//
	//Input clock fre=16MHz
	// In this case, we'll use a speed of 125 kbit/s, 250 kbit/s, 500 kbit/s.
	// If we set the length of the propagation segment to 7 bit time quanta,
	// and we set both the phase segments to 4 quanta each,
	// one bit will be 1+7+4+4 = 16 quanta in length.
	//
	// setting the prescaler (BRP) to 0 => 500 kbit/s.
	// setting the prescaler (BRP) to 1 => 250 kbit/s.
	// setting the prescaler (BRP) to 3 => 125 kbit/s.
	//
	// If we set the length of the propagation segment to 3 bit time quanta,
	// and we set both the phase segments to 1 quanta each,
	// one bit will be 1+3+2+2 = 8 quanta in length.
	// setting the prescaler (BRP) to 0 => 1 Mbit/s.

	// Go into configuration mode
	MCP2510_Write(MCP2510REG_CANCTRL, MODE_CONFIG);

	//if( MCP2510_DEBUG )  printf( "MCP2510REG_CANCTRL =  0x%x\n", MCP2510_Read(MCP2510REG_CANCTRL) );

	while( ReadBackCNT<8 )
	{
		value = ( MCP2510_Read( MCP2510REG_CANSTAT ) & 0xe0 );
		if(value == MODE_CONFIG ){
			//printf( "ReadBackCNT = 0x%x\n", ReadBackCNT );
			break;
		}
		ReadBackCNT++ ;
	}
	
	if( ReadBackCNT == 8 ) 			//Set mcp2510's mode failed,redo it again
	{
		printf( "Set config mode is failed! CANCTRL = 0x%x\n", value );
		MCP2510_Reset();
		MCP2510_Write(MCP2510REG_CANCTRL, MODE_CONFIG);		//redo to set mcp2510 mode
		delay( 150 );
		value = ( MCP2510_Read(MCP2510REG_CANCTRL) & 0xe0 );	//read back mode from CANSTAT Register
		printf( "Set is 0x%x , Read is 0x%x\n", MODE_CONFIG, value ) ;
	}

	switch(bandrate){
	case BandRate_10kbps:
		MCP2510_Write(CNF1, 0x31);	//10k	16TQ
		MCP2510_Write(CNF2, 0xb0);  //PS1=7 TQ  PSeg=1 TQ
		MCP2510_Write(CNF3, 0x06);  //PS2=7 TQ SYNC=1 TQ	
		//if( MCP2510_DEBUG )  printf( "CNF1 =  0x%x\n", MCP2510_Read(CNF1) );
		//if( MCP2510_DEBUG )  printf( "CNF2 =  0x%x\n", MCP2510_Read(CNF2) );
		//if( MCP2510_DEBUG )  printf( "CNF3 =  0x%x\n", MCP2510_Read(CNF3) );
		break;
	case BandRate_125kbps:
		MCP2510_Write(CNF1, SJW1|BRP4);	//Synchronization Jump Width Length =1 TQ
		MCP2510_Write(CNF2, BTLMODE_CNF3|(SEG4<<3)|SEG7); // Phase Seg 1 = 4, Prop Seg = 7
		MCP2510_Write(CNF3, SEG4);// Phase Seg 2 = 4
		break;
	case BandRate_250kbps:
		MCP2510_Write(CNF1, SJW1|BRP2);	//Synchronization Jump Width Length =1 TQ
		MCP2510_Write(CNF2, BTLMODE_CNF3|(SEG4<<3)|SEG7); // Phase Seg 1 = 4, Prop Seg = 7
		MCP2510_Write(CNF3, SEG4);// Phase Seg 2 = 4
		break;
	case BandRate_500kbps:
		MCP2510_Write(CNF1, SJW1|BRP1);	//Synchronization Jump Width Length =1 TQ
		MCP2510_Write(CNF2, BTLMODE_CNF3|(SEG4<<3)|SEG7); // Phase Seg 1 = 4, Prop Seg = 7
		MCP2510_Write(CNF3, SEG4);// Phase Seg 2 = 4
		break;
	case BandRate_1Mbps:
		MCP2510_Write(CNF1, SJW1|BRP1);	//Synchronization Jump Width Length =1 TQ
		MCP2510_Write(CNF2, BTLMODE_CNF3|(SEG3<<3)|SEG2); // Phase Seg 1 = 2, Prop Seg = 3
		MCP2510_Write(CNF3, SEG2);// Phase Seg 2 = 1
		break;