i2c_24c04.c

用ARM7 LPC2292芯片驱动240128图形点阵液晶的源代码

/*****************************************************************************
 *   i2c.c:  I2C C file for Philips LPC214x Family Microprocessors
 *
 *   Copyright(C) 2006, Philips Semiconductor
 *   All rights reserved.
 *
 *   History
 *   2005.10.01  ver 1.00    Prelimnary version, first Release
 *
*****************************************************************************/
#include "LPC213x.h"                        /* LPC21xx definitions */
#include "type.h"
#include "irq.h"
//#include "i2c.h"

#define BUFSIZE			0x20
#define MAX_TIMEOUT		0x00FFFFFF

#define I2CMASTER		0x01
#define I2CSLAVE		0x02

/* For more info, read Philips's SE95 datasheet */
#define SE95_ADDR		0x9E
#define SE95_ID			0x05
#define SE95_CONFIG		0x01
#define SE95_TEMP		0x00
#define RD_BIT			0x01

#define GET_DEVICE_ID		0x01
#define GET_TEMPERATURE		0x02
#define SET_CONFIGURATION	0x03

#define I2C_IDLE		0
#define I2C_STARTED		1
#define I2C_RESTARTED		2
#define I2C_REPEATED_START	3
#define DATA_ACK		4
#define DATA_NACK		5

#define I2CONSET_I2EN		0x00000040  /* I2C Control Set Register */
#define I2CONSET_AA		0x00000004
#define I2CONSET_SI		0x00000008
#define I2CONSET_STO		0x00000010
#define I2CONSET_STA		0x00000020

#define I2CONCLR_AAC		0x00000004  /* I2C Control clear Register */
#define I2CONCLR_SIC		0x00000008
#define I2CONCLR_STAC		0x00000020
#define I2CONCLR_I2ENC		0x00000040

#define I2DAT_I2C		0x00000000  /* I2C Data Reg */
#define I2ADR_I2C		0x00000000  /* I2C Slave Address Reg */
#define I2SCLH_SCLH		0x000000c8  /* I2C SCL Duty Cycle High Reg */
#define I2SCLL_SCLL		0x000000c8  /* I2C SCL Duty Cycle Low Reg */

/*
DWORD I2CMasterState = I2C_IDLE;
DWORD I2CSlaveState = I2C_IDLE;

DWORD I2CCmd;
DWORD I2CMode;

BYTE I2CMasterBuffer[BUFSIZE];
BYTE I2CSlaveBuffer[BUFSIZE];
DWORD I2CCount = 0;
DWORD I2CReadLength;
DWORD I2CWriteLength;

DWORD RdIndex = 0;
DWORD WrIndex = 0;
*/
BYTE IIC_Chip_Addr;					//第一个送至24C04的数据
									//为24C04的地址以及读写操作的最高位地址，及读写控制信号
BYTE IIC_Addr;						//第二个送至24C04的数据
									//为读写操作的地址数据
BYTE IIC_Byte_Number;				//数据个数
BYTE IIC_Data;						//数据缓冲器
BOOL IIC_Busy = FALSE;					//IIC忙标志位

/* 
From device to device, the I2C communication protocol may vary, 
in the example below, the protocol uses repeated start to read data from or 
write to the device:
For master read: the sequence is: STA,Addr(W),offset,RE-STA,Addr(w),data...STO 
for master write: the sequence is: STA,Addr(W),length,RE-STA,Addr(r),data...STO
Thus, in state 8, the address is always WRITE. in state 10, the address could 
be READ or WRITE depending on the I2CCmd.
*/   

/*****************************************************************************
** Function name:		I2C0MasterHandler
**
** Descriptions:		I2C0 interrupt handler, deal with master mode
**				only.
**
** parameters:			None
** Returned value:		None
** 
*****************************************************************************/
void I2C0MasterHandler (void) __irq 
{
    BYTE StatValue;

    /* this handler deals with master read and master write only */
    StatValue = I2C0STAT; 		//读取IIC状态，以便后面针对不同状态进行分支处理
//    IENABLE;
	//
    switch ( StatValue )
    {
		case 0x08:		//IIC 启动条件已发送完毕，紧接要发送从器件地址
			I2C0DAT = IIC_Chip_Addr&(~0x01);//I2CMasterBuffer[0];  //发送从器件地址以及读写标志位
			I2C0CONCLR = (I2CONCLR_SIC | I2CONCLR_STAC);	//清标志
			break;
	
		case 0x10:		//读操作重发，当读操作时，在启动条件后发送完从器件地址
			I2C0DAT = IIC_Chip_Addr;
			I2C0CONCLR = (I2CONCLR_SIC | I2CONCLR_STAC);
			break;
	
		case 0x18:		//从器件地址发送完后，接收到ACK，接着要发送操作地址
	    	I2C0DAT = IIC_Addr;
			I2C0CONCLR = I2CONCLR_SIC;
			break;
	   case 0x20:
	   		I2C0CONSET = I2CONSET_STO;//
			I2C0CONSET = I2CONSET_STA;
			I2C0CONCLR = I2CONCLR_SIC;
			break;

		case 0x28:	/* Data byte has been transmitted, regardless ACK or NACK */
		case 0x30:
			if(IIC_Byte_Number)
			{
				if(IIC_Chip_Addr&0x01)
				{
					I2C0CONSET = I2CONSET_STA;	//读重发	
				}
				else
				{
					I2C0DAT = IIC_Data;			//发送有效数据
					IIC_Byte_Number--;
				}
			}
			else
			{
				if(IIC_Chip_Addr&0x01)
				{
					I2C0CONSET = I2CONSET_STA;	//读重发	
				}
				else
				{
					I2C0CONSET = I2CONSET_STO;//
					IIC_Busy = FALSE;
				}
			}
		
			I2C0CONCLR = I2CONCLR_SIC;
			break;
		case 0x40:	//主接收器，读重发已发完，收到ACK，这里将设置在接收到数据后发NACK
			I2C0CONCLR = I2CONCLR_AAC;
			I2C0CONCLR = I2CONCLR_SIC;
			break;
	
		case 0x50:	/* Data byte has been received, regardless following ACK or NACK */
		case 0x58:
			IIC_Data = I2C0DAT;
			IIC_Busy = FALSE;
			//这里也一样，应将IIC停掉
//			I2C0CONSET = I2CONSET_AA;	/* assert ACK after data is received */
			I2C0CONSET = I2CONSET_STO;
			I2C0CONCLR = I2CONCLR_SIC;
			while( I2C0CONSET & I2CONSET_STO );
			break;

		case 0x48:
			I2C0CONSET = I2CONSET_STO;//
			I2C0CONSET = I2CONSET_STA;
			I2C0CONCLR = I2CONCLR_SIC;
			break;
	
		case 0x38:
		default:
			I2C0CONSET = I2CONSET_STO;//
			I2C0CONCLR = I2CONCLR_SIC;	
			break;
    }
 //   IDISABLE;
    VICVectAddr = 0;		/* Acknowledge Interrupt */
}

/*****************************************************************************
** Function name:		I2CStart
**
** Descriptions:		Create I2C start condition, a timeout
**				value is set if the I2C never gets started,
**				and timed out. It's a fatal error. 
**
** parameters:			None
** Returned value:		true or false, return false if timed out
** 
*****************************************************************************/
/*
DWORD I2CStart( void )
{
    DWORD timeout = 0;
    DWORD returnValue = FALSE;
 
    //--- Issue a start condition ---
    I2C0CONSET = I2CONSET_STA;	// Set Start flag //
    
    //--- Wait until START transmitted ---
    while( 1 )
    {
		if ( I2CMasterState == I2C_STARTED )
		{
	   	 	returnValue = TRUE;
	    	break;	
		}
		if ( timeout >= MAX_TIMEOUT )
		{
	   	 	returnValue = FALSE;
	    	break;
		}
		timeout++;
    }
    return ( returnValue );
}
*/
/*****************************************************************************
** Function name:		I2CStop
**
** Descriptions:		Set the I2C stop condition, if the routine
**				never exit, it's a fatal bus error.
**
** parameters:			None
** Returned value:		true or never return
** 
*****************************************************************************/
/*
DWORD I2CStop( void )
{
    I2C0CONSET = I2CONSET_STO;      // Set Stop flag 
    I2C0CONCLR = I2CONCLR_SIC;  // Clear SI flag 
            
    //--- Wait for STOP detected ---
    while( I2C0CONSET & I2CONSET_STO );
    return TRUE;
}*/

/*****************************************************************************
** Function name:		I2CInit
**
** Descriptions:		Initialize I2C controller
**
** parameters:			I2c mode is either MASTER or SLAVE
** Returned value:		true or false, return false if the I2C
**				interrupt handler was not installed correctly
** 
*****************************************************************************/
DWORD I2CInit( void) 
{
    PINSEL0 = 0x50;	/* set PIO0.2 and PIO0.3 to I2C0 SDA and SCK */
    IODIR0 = 0x0C;	/* set port 0.2 and port 0.3 to output, high */
    IOSET0 = 0x0C;

    I2C0CONCLR = I2CONCLR_AAC | I2CONCLR_SIC | I2CONCLR_STAC | I2CONCLR_I2ENC;    

    I2C0SCLL   = I2SCLL_SCLL;
    I2C0SCLH   = I2SCLH_SCLH;

    if ( install_irq( I2C0_INT, (void *)I2C0MasterHandler ) == FALSE )
    {
		return( FALSE );
    }
    I2C0CONSET = I2CONSET_I2EN;
    return( TRUE );
}
//=====================================================================//
//函数：char SM_Receive (unsigned int byte_address)
//描述：读单字节数据从指定的AT24C04的地址空间
//参数：byte_address	地址，9位有效	
//返回：Dat		数据
//注意：无        
//=====================================================================//
unsigned char SM_Receive (unsigned int byte_address)
{
	unsigned char ucTemp;
	ucTemp = (unsigned char)(byte_address>>7);
	ucTemp = ucTemp&0x02;
	while (IIC_Busy); 					// 等待总线空闲
//	I2CMasterState = I2C_IDLE;
	IIC_Busy = TRUE; 						//占用SMBus（设置为忙）
//	SMB0CN = 0x44; 						// 允许SMBus，应答周期发ACK
	IIC_Byte_Number = 1; 					// 1 地址字节
	IIC_Chip_Addr = (0xA0|0x01|ucTemp); 		// 片选+ READ + 一个高位的地址
	IIC_Addr = (unsigned char)(byte_address&0x00FF); // 8 位地址
	I2C0CONSET = I2CONSET_STA;//I2CStart(); 							// 启动传输过程
	while (IIC_Busy==TRUE); 					// 等待传输结束
	while( I2C0CONSET & I2CONSET_STO );
	return IIC_Data;
}
//=====================================================================//
//函数：void SM_Send (unsigned int byte_address, unsigned char out_byte)
//描述：写单字节数据至指定的AT24C04的地址空间
//参数：byte_address	地址，9位有效
//		out_byte		数据
//返回：无
//注意：无        
//=====================================================================//
// SMBus 字节写函数-----------------------------------------------------
void SM_Send (unsigned int byte_address, unsigned char out_byte)
{
	unsigned char ucTemp;
	ucTemp = (unsigned char)(byte_address>>7);
	ucTemp = ucTemp&0x02;
	while (IIC_Busy==TRUE); 			// 等待SMBus 空闲
	IIC_Busy = 1; 						// 占用SMBus（设置为忙）

	IIC_Byte_Number = 1; 					// 1 地址字节
	IIC_Chip_Addr = (0xA0|ucTemp); 		// 片选+ READ + 一个高位的地址
	IIC_Addr = (unsigned char)(byte_address&0x00FF); // 8 位地址
	IIC_Data = out_byte; 					// 待写数据
	I2C0CONSET = I2CONSET_STA;//I2CStart(); 							// 启动传输过程
	while (IIC_Busy==TRUE); 					// 等待传输结束
	while( I2C0CONSET & I2CONSET_STO );
}
/*****************************************************************************
** Function name:		I2CEngine
**
** Descriptions:		The routine to complete a I2C transaction
**				from start to stop. All the intermitten
**				steps are handled in the interrupt handler.
**				Before this routine is called, the read
**				length, write length, I2C master buffer,
**				and I2C command fields need to be filled.
**				see i2cmst.c for more details. 
**
** parameters:			None
** Returned value:		true or false, return false only if the
**				start condition can never be generated and
**				timed out. 
** 
*****************************************************************************/
/*
DWORD I2CEngine( void ) 
{
    I2CMasterState = I2C_IDLE;
    RdIndex = 0;
    WrIndex = 0;
    if ( I2CStart() != TRUE )
    {
	I2CStop();
	return ( FALSE );
    }
    while ( 1 )
    {
	if ( I2CMasterState == DATA_NACK )
	{
	    I2CStop();
	    break;
	}
    }    
    return ( TRUE );      
}  */