com_i2c.c

厂家提供的OSD芯片T108的驱动程序,驱动模拟屏

#include "reg51.h"
#include "common.h"
#include "COM_I2C.h"
//----------------------------------------
// S_Condition for TWD protocol
//----------------------------------------
void StartCondition(void)
{
    uCHAR ix;
    uCHAR cTWtrytime=0;
    //EA=0;
    while(++cTWtrytime)
    {
        Set_SDA_High;
        Set_SCL_High;        /* make sure two line is release */
        for(ix = 0; ix < TWD_LONG_TIME; ix++)
        { };  /* Delay 12us */

        Set_SDA_Low;
        for(ix = 0; ix < TWD_LONG_TIME; ix++)
        { };  /* Delay 12us */

        if((SCL_High)&&(SDA_Low))
            break;
    }

    for(ix = 0; ix < TWD_SHORT_TIME; ix++)
    { };  /* Delay 12us */
}

//----------------------------------------
// P_Condition for TWD protocol
//----------------------------------------
void StopCondition(void)
{
    uCHAR ix;
    uCHAR cTWtrytime=0;

    Set_SDA_Low;
    Set_SCL_High;
    for(ix = 0; ix < TWD_SHORT_TIME; ix++)
    { };  /* delay 12us */

    //while(SCL_Low && ++cTWtrytime)
    //{ };

    for(ix = 0; ix < TWD_SHORT_TIME; ix++)
    { };  /* delay 12us */

    Set_SDA_High;
    for(ix = 0; ix < TWD_SHORT_TIME; ix++)
    { };  /* delay 12us */
	//EA=1;
}

//--------------------------------------------------
// Send_Byte
//    Send a byte to master with a acknowledge bit
//--------------------------------------------------
uCHAR Send_Byte(uCHAR cData)
{
    uCHAR ix, j, cAcknowledge;
    uCHAR cTWtrytime=0;

    cAcknowledge = 0;

    for(ix = 0; ix < 8; ix++)
    {
        Set_SCL_Low;
        for(j = 0; j < TWD_SHORT_TIME; j++)
        { };

        if(cData&0x80)Set_SDA_High;
		    else Set_SDA_Low;
		    cData<<=1;

        for(j = 0; j < TWD_SHORT_TIME; j++)
        { };

        Set_SCL_High;
        //while(SCL_Low && ++cTWtrytime)
        //{ };

        for(j = 0; j < TWD_SHORT_TIME; j++)
        { };
    }
    for(j = 0; j < TWD_SHORT_TIME; j++)
    { };

    Set_SCL_Low;
    for(j = 0; j < TWD_SHORT_TIME; j++)
    { };

    Set_SDA_High;                /* release data line for acknowledge */
    for(j = 0; j < TWD_SHORT_TIME; j++)
    { };

    Set_SCL_High;                /* Send a clock for Acknowledge */
    //while(SCL_Low)
    //{ };
    for(j = 0; j < TWD_SHORT_TIME; j++)
    { };

    if(SDA_High) 
       cAcknowledge = 1; /* No Acknowledge */
    Set_SCL_Low;                   /* Finish Acknoledge */
    for(j = 0; j < TWD_SHORT_TIME; j++)
    { };

    return(cAcknowledge);
}



//--------------------------------------------------
// Read_Byte
//    Read a byte from master with a acknowledge bit
//--------------------------------------------------
uCHAR Read_Byte(uCHAR cNum)
{
    uCHAR ix, j;
    uCHAR cRetval=0;

    for(ix=0;ix<8;ix++){
          Set_SCL_High;
          //while(SCL_Low){};
          for(j=0;j<TWD_SHORT_TIME;j++){};
          cRetval = (SDA_High)? (cRetval|(1<<(7-ix))):cRetval ;  /* MSB First */
	  Set_SCL_Low;
     }

     if(cNum==1)
     	Set_SDA_High;
     else
		Set_SDA_Low;
     //SDA = (cNum==1) 1:0;
     Set_SCL_High;
     //while(SCL_Low){};
     for(j = 0; j < TWD_SHORT_TIME; j++)
     { };

    Set_SCL_Low;

    Set_SDA_High;
    for(j = 0; j < TWD_SHORT_TIME; j++)
    { };

    return cRetval;
}

//--------------------------------------------------
// Read Byte to Device
//--------------------------------------------------
uCHAR I2CReadByte(uCHAR cDevAddr, uCHAR cReg)
{
    uCHAR cResult = 0;


    /* write reg offset */
    StartCondition();
    if(Send_Byte(cDevAddr))
	return 0;  // Write address
    if(Send_Byte(cReg))
	return 0;

    /* read data */
    StartCondition();
    if (Send_Byte(cDevAddr | 0x01)) // Read address
	return 0;
    cResult = Read_Byte(1);

    StopCondition();
    return cResult;
}


uCHAR I2CWriteByte(uCHAR cDevAddr, uCHAR cReg, uCHAR cData)
{


    /* start condition */
    StartCondition();
  cDevAddr &= 0xFE;   // Force WRITE address
    /* send device ID and write data */
    if(!Send_Byte(cDevAddr))
    {
        if(!Send_Byte(cReg))
        {
            if(!Send_Byte(cData))
            {
                StopCondition();
                return(0);      /* success */
            }
        }
    }
    StopCondition();
    return(1);
}

//--------------------------------------------------
// 041901, Added for TWD Burst Write
// 1. PT8655X_Wr_Burst_A    (Start + Slave_ID + Address)
// 2. PT8655X_Wr_Burst_D    (Data)
// 3. PT8655X_Wr_Burst_P    (stop)
//--------------------------------------------------
uCHAR twdWr_Burst_A(uCHAR cReg)
{
    StartCondition();
    if(!Send_Byte(TW803_P0))
    {
        if(!Send_Byte(cReg))
        {
            return(0);               //
        }
    }
    return(1);                  //
}


void twdWr_Burst_D(uCHAR cData)
{
    uCHAR ix;

    for(ix = 0; ix < 8; ix++)
    {
        Set_SCL2Low;
        if(cData&0x80)Set_SDA2High;
		else Set_SDA2Low;
		cData<<=1;
        Set_SCL2High;
    }
    Set_SCL2Low;
    Set_SDA2High;                /* release data line for acknowledge */
    Set_SCL2High;                /* Send a clock for Acknowledge */
    Set_SCL2Low;                   /* Finish Acknoledge */
}

void twdWr_Burst_P(void)
{
    StopCondition();
}

//twdWriteTable() is used for burst write for
//any I2C standar device

void OSDSetRamDataBuest(uWORD wdata)			//add for new version
{
	twdWr_Burst_D((uCHAR)(wdata & 0xff));
	twdWr_Burst_D((uCHAR)(wdata>>8));		 	
}
//--------------------------------------------------
// Write Multiple Bytes to Device
//--------------------------------------------------


void twdDelay(uWORD wLoops)
{
	uWORD wTemp;

    while (wLoops--) {
	    wTemp = 1000/6;	// one loop below takes about 11 us
        while (wTemp--);
    }
}



// OSD config register Write
void OSD1CfgWr(uCHAR index,uCHAR dat)
{
    I2CWriteByte(TW803_P0,OSD_CFG_INDEX,index);
    I2CWriteByte(TW803_P0,OSD_CFG_DATA,dat);
}

void OSD1SetRamAddr(uWORD address)
{	
  	I2CWriteByte(TW803_P0,OSD_RAM_AL,(uCHAR)(address & 0xff));  
	  I2CWriteByte(TW803_P0,OSD_RAM_AH,(uCHAR)(address>>8));
}

void OSD1SetRamData(uWORD wdata)
{
	  I2CWriteByte(TW803_P0,OSD_RAM_DL,(uCHAR)(wdata & 0xff));
  	I2CWriteByte(TW803_P0,OSD_RAM_DH,(uCHAR)(wdata>>8));
} 


// OSD2 config register Write
void OSD2CfgWr(uCHAR index,uCHAR dat)
{
	  I2CWriteByte(TW803_P0,OSD2_CFG_INDEX,index);
	  I2CWriteByte(TW803_P0,OSD2_CFG_DATA,dat);
}


void OSD2SetRamAddr(uWORD address)
{
	  I2CWriteByte(TW803_P0,OSD2_RAM_AL,(uCHAR)(address & 0xff));
  	I2CWriteByte(TW803_P0,OSD2_RAM_AH,(uCHAR)(address>>8));

}

void OSD2SetRamData(uWORD wdata)
{
	  I2CWriteByte(TW803_P0,OSD2_RAM_DL,(uCHAR)(wdata & 0xff));		
  	I2CWriteByte(TW803_P0,OSD2_RAM_DH,(uCHAR)(wdata>>8));	
}




void serial_Init(void)
{

}


/*
unsigned char c2n(unsigned char keyv)
{
    keyv = keyv;
		return 1;
}
unsigned char n2c(unsigned char hexv)
{
	  hexv = hexv;
		return 1;
}


void putByte(unsigned char cByte)
{
    cByte = cByte;
}
*/

/*
void putValue(unsigned char *sStr,unsigned char cByte,bit crlf)
{
    uCHAR *str;

    str  = sStr;
		cByte = cByte;
		crlf  = crlf;
}


unsigned char getByte(void)
{
    return 1;
}


void putString(unsigned char *puts)
{
    uCHAR *str;

    str = puts;
}
*/
/*
void I2CRd(unsigned char host,unsigned char addr)
{
    host = host;
		addr = addr;
}

void I2CWt(unsigned char host,unsigned char addr,unsigned char valu)
{
    host = host;
		addr = addr;
		valu = valu;
}

void serial_Debug(void)
{

}
*/