ddc2bi.c

完整的软件学习--显示器驱动视频软件

			}
			else
			{
				DDC2Bi_InitRx ();
			}
			
			break;
					// 
		case DDC2B_SRCADDRESS:
						// get the length
			rxLength = rxByte & ~DDC2Bi_CONTROL_STATUS_FLAG;
					// put the received byte in DDCBuffer
			DDCBuffer[rxIndex++] = rxByte;
			rxChkSum ^= rxByte;
			// set the receive body state
			rxStatus++;// = DDC2B_COMMAND;
						//if it is a NULL message
			if (rxLength == 0 || rxLength >= MaxBufLen)
			{
				rxStatus=DDC2B_COMPLETED;
				Set_RxBusyFlag();
			}
			break;
					// get the command
		case DDC2B_COMMAND:
						// save the commandbyte
			rxStatus++;// = DDC2B_RECBODY;
				// get the message body
		case DDC2B_RECBODY:
			DDCBuffer[rxIndex++] = rxByte;

			rxChkSum ^= rxByte;
			rxLength--;
				// the last byte in the message body
			if (rxLength == 0)
			{
				rxStatus++;// = DDC2B_WAITFORCK;
			}
			break;
					// ...here we are waiting for checksum...
		case DDC2B_WAITFORCK:
			// if checksum match
			if (rxChkSum == rxByte)
			{
				if(intype==0)
					RxInputPort = 0;
				else
					RxInputPort = 1;
				rxStatus = DDC2B_COMPLETED;
				Set_RxBusyFlag();
			}
			// elsechecksum error
			else
			{
				// if checksum error re-initialize the receive buffer
				DDC2Bi_InitRx ();
			}
			break;
		default:
						// clear the rxState and the current buffer for a new message
			if (!RxBusyFlag)
				DDC2Bi_InitRx ();
			break;
		}
			
		intFlag &= (~RCBI); //clear interrupt flag
		break;	
    	}
    }

}



void EXT1Interrupt(void) interrupt 2
{   

	EX1=0;
}


#endif // Albert
#endif

/*
#else  


void	DDC2Bi_InitRx (void)
{
	// clear the rxState
	rxStatus = DDC2B_CLEAR;
	// the current buffer for a new message
	rxIndex = 0;
}

void	DDC2Bi_Init (void)
{
	// initialize various flags and data items
	
	DDC2Bi_InitRx ();
	txStatus   = DDC2B_CLEAR;		// initialize transmit status

	// enable the DDC2Bi(SlaveB) port
	SLVBADDR = 0xB7; //Bit7: enable slaveB IIC(0x6e) 0x80|(0x6e<<1)
	PADMOD2 = 0x80; //Set P3.4 P3.5 as Hsda/Hclk

	// set the EX1 priority to HIGH
	PX1 = 1;
	// enable IRQ1 interrupt level
	EX1	= 1;
	// initialize the transmit communication, so that either a valid
	// or a NULL message is sent on a request from host
	txBufferPtr = &nullMsg1[0];
	
	txLength = sizeof (nullMsg1);
	RCBTXBBUF = *txBufferPtr++;
	
}


void	DDC2Bi_GetTxBuffer (void)
{ BYTE	i;								// loop variable
  for ( i=MAX_TXWAIT_DELAY; i>0; i--)
    if (txStatus == DDC2B_MSGON)
    	{ 
	      Delay1ms(1);
    	}
  txStatus = DDC2B_CLEAR;
}

BYTE DDC2Bi_ComputeChecksum(BYTE count)
{
	BYTE	checksum = INITTxCK;
	BYTE	i = 0;
	for ( ; count>0; count--)
		checksum ^= DDCBuffer[i++];
	return checksum;
}

void DDC2Bi_MessageReady (void)
{ 
  //DDCBuffer[0] |= DDC2Bi_CONTROL_STATUS_FLAG;
  // compute the check sum and assign to tx buffer
  DDCBuffer[(DDCBuffer[0] & ~DDC2Bi_CONTROL_STATUS_FLAG) + 1] = 
  DDC2Bi_ComputeChecksum ((DDCBuffer[0] & ~DDC2Bi_CONTROL_STATUS_FLAG) + 1);
  //DDCBuffer[9] = DDC2Bi_ComputeChecksum(9);
  // wait until old packet sent out
  //DDCBuffer[10] = 0x6e;
  DDC2Bi_GetTxBuffer ();
  
  //DDCBuffer[9] = 0x50;
  // 
  EA = 0;
  txBufferPtr = &DDCBuffer[0];
  txLength = (DDCBuffer[0] & (~DDC2Bi_CONTROL_STATUS_FLAG)) + 2;
  // re enable interrupts
  EA = 1;
}

void	DDC2Bi_ParseCommand (void)
{
	BYTE length;//, command;
	
	length = DDCBuffer[LENGTH] & 0x7F;
	
	if(rxIndex <= 0) return;

	if(length <= 0) 
	{
		EA = 0;
  		txBufferPtr = &nullMsg1[1];
  		txLength = sizeof (nullMsg1);
  		// re enable interrupts
  		EA = 1;
  		RCBTXBBUF = DDC2B_DEST_ADDRESS;
  		return;
	}

   //----------------------
#if 0
    if(mStar_ReadOSDByte(IOSDC1)&0x01)
    {   //Draw_RootMenu();
   		MenuPageIndex=RootMenu;
   		MenuItemIndex=0;
        ExecuteKeyEvent(MIA_RedrawMenu);
    }
#endif
	
   //Osd_Hide();
#if 1
	length = AlignControl();
#endif
	if(length <= 0) 
	{
		DDCBuffer[0] = 0x80;
	}
	else if(length == 0xFE || length == 0xFD)
	{
		DDCBuffer[0] = 0x80;	
		//return;
	}
	
	DDC2Bi_MessageReady();
	RCBTXBBUF = DDC2B_DEST_ADDRESS;
	
}

void DDC2Bi_CommandHandler (void)
{
	BYTE index;
	if (rxStatus == DDC2B_COMPLETED)
	{
		INTEN=0x00;
		index=0;

#if 0//def Debug DDC
		Osd_SetTextColor(1, rxIndex);
		Osd_DrawHex(0, 0, CmIndex++);
		for (index=0; index<rxIndex; index++)			
			Osd_DrawHex(3, index+0, DDCBuffer[index]);
#endif

		DDC2Bi_ParseCommand ();
		Clr_RxBusyFlag();
		DDC2Bi_InitRx ();
		INTEN=0xC6; //0xc0;
	}
}

void EXT1Interrupt(void) interrupt 2
{   BYTE intFlag, rxByte;

    EX1=0;
    intFlag=INTFLG;
    if ( intFlag)
    {
		switch (intFlag & (WslvA1 | WslvA2))
		{
			case WslvA1:
				RewriteDDC_A1=1;
				INTFLG &= (~WslvA1); //clear interrupt flag
				break;
			case WslvA2:
				RewriteDDC_A2=1;
				INTFLG &= (~WslvA2); //clear interrupt flag
				break;
		}
		switch (intFlag & (TXBI | RCBI ))
		{
	    	case TXBI:
				txStatus = DDC2B_MSGON;
						// no characters left
				if (!(txLength))
				{
							// clear the transmit status
					txStatus = DDC2B_CLEAR;
					RCBTXBBUF = 0;
					EX1=1;
					return ;		
				}
						// send out the current byte
				RCBTXBBUF = *txBufferPtr++;
				txLength--;
				INTFLG &= (~TXBI); //clear interrupt flag
				break;

		case RCBI:
					// read the received byte
			rxByte = RCBTXBBUF;
					// depending of the message status
			switch (rxStatus)
			{
						// in case there is nothing received yet
				case DDC2B_CLEAR:
					if (rxByte == DDC2B_SRC_ADDRESS)
					{
						rxStatus++;// = DDC2B_SRCADDRESS;
						rxChkSum = INITRxCK;
					}
					else
					{
						DDC2Bi_InitRx ();
					}
					break;
				case DDC2B_SRCADDRESS:
					//   Power_TurnOffGreenLed(); // turn off green led   // jeff add it 11 24
		           // Power_TurnOnAmberLed(); 
								// get the length
					rxLength = rxByte & ~DDC2Bi_CONTROL_STATUS_FLAG;
							// put the received byte in DDCBuffer
					DDCBuffer[rxIndex++] = rxByte;
					rxChkSum ^= rxByte;
					// set the receive body state
					rxStatus++;// = DDC2B_COMMAND;
								//if it is a NULL message
					if (rxLength == 0 || rxLength >= MaxBufLen)
					{
									// wait for CK
						//rxStatus++;// = DDC2B_RECBODY;
						//rxStatus++;// = DDC2B_WAITFORCK;
						rxStatus=DDC2B_COMPLETED;
						Set_RxBusyFlag();
					}
					break;
							// get the command
				case DDC2B_COMMAND:
								// save the commandbyte
					rxStatus++;// = DDC2B_RECBODY;
						// get the message body
				case DDC2B_RECBODY:
					DDCBuffer[rxIndex++] = rxByte;
					rxChkSum ^= rxByte;
					rxLength--;
						// the last byte in the message body
					if (rxLength == 0)
					{
#if 1			
						rxStatus++;// = DDC2B_WAITFORCK;
#else				
						rxStatus=DDC2B_COMPLETED;
						Set_RxBusyFlag();
#endif
					}
					break;
							// ...here we are waiting for checksum...
#if 1
				case DDC2B_WAITFORCK:
					// if checksum match
					if (rxChkSum == rxByte)
					{
						rxStatus = DDC2B_COMPLETED;
						Set_RxBusyFlag();
					}
					// elsechecksum error
					else
					{
						// if checksum error re-initialize the receive buffer
						DDC2Bi_InitRx ();
					}
					break;
#endif
							// error condition
				default:
								// clear the rxState and the current buffer for a new message
					if (!RxBusyFlag)
						DDC2Bi_InitRx ();
					break;
			}
			INTFLG &= (~RCBI); //clear interrupt flag
			break;	
    	}
    }
	EX1=1;
//	EA=1;
}
#endif

BYTE AlignControl(void)
{ 
	return 0;	
}


*/