parallel.cpp

使用VC6开发 通过并口操作IIC 使用winio驱动操作并口

// parallel.cpp: implementation of the parallel class.
// p25.1:SCL
// P25.2:SDA OUT
// P25.13:SDA IN
// output is reversed bit by bit.
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "IIC.h"
#include "parallel.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

parallel::parallel()
{
	mPortAddr = 0x0378;
	m_bFlag = InitializeWinIo();
	WriteByte(0xff);
	m_Speed = 0;
	m_bSwapLine = FALSE;
	m_bBusy = false;
	m_bBusState = false;
}

parallel::parallel(WORD PortAddr)
{
	parallel();
	mPortAddr = PortAddr;
}

parallel::~parallel()
{
	WriteByte(0xff);
	ShutdownWinIo();
}

void parallel::InitPort()
{
	WriteByte(0xff);
}

void parallel::Init(BYTE value)
{
	WriteByte(value);
}

void parallel::WriteByte(BYTE Value)
{
/*Use WINIO.LIB's function.
SetPortVal(
WORD wPortAddr,       
DWORD dwPortVal,      
BYTE bSize//Can be 1 (BYTE), 2 (WORD) or 4 (DWORD). 
);               	
	*/
	BYTE tmp = 0;
	if(m_bSwapLine){//Swap SDA & SCL
		tmp = (Value<<7)>>6;
		tmp += (Value<<6)>>7;
		Value = Value&0xFC;
		Value = Value|tmp;
	}
	DWORD dwPortVal = (DWORD)(~Value);
//	for(int i =0;i<5;i++)
		SetPortVal(mPortAddr,dwPortVal,1);
}

BYTE parallel::ReadByte()
{
/*bool _stdcall GetPortVal(
WORD wPortAddr,       
PDWORD pdwPortVal,    
BYTE bSize//Can be 1 (BYTE), 2 (WORD) or 4 (DWORD). 
	);*/
	DWORD Value=0;
//	WORD ReadAddr = mPortAddr + 1;
	WORD ReadAddr = 0x0379;
	GetPortVal(ReadAddr,&Value,1);//read byte
	return (BYTE)(~Value);
}

void parallel::SendStart()
{
	m_bBusy = true;
	WriteByte(0x03);// SCL = 1;SDA = 1;
	WriteByte(0x03);// SCL = 1;SDA = 1;
	WriteByte(0x01);// SCL = 1;SDA = 0;
	WriteByte(0x01);// SCL = 1;SDA = 0;
	WriteByte(0x00);// SCL = 0;SDA = 0;
	WriteByte(0x00);// SCL = 0;SDA = 0;
}

void parallel::SendStop()
{
	WriteByte(0x00);// SCL = 0;SDA = 0;
	WriteByte(0x00);// SCL = 0;SDA = 0;
	WriteByte(0x01);// SCL = 1;SDA = 0;
	WriteByte(0x01);// SCL = 1;SDA = 0;
	WriteByte(0x03);// SCL = 1;SDA = 1;
	WriteByte(0x03);// SCL = 1;SDA = 1;
	m_bBusy = false;
}

BOOL parallel::SendByte(BYTE byte)//bit7-bit0-ack
{
	BYTE bit = 0;
	BOOL flag = false;
	for(int i = 0;i < 8;i++){
		if((byte&(0x80>>i))!=0)
			bit = 2;
		else
			bit = 0;
		WriteByte((0|bit));
		WriteByte((0|bit));//SCL = 0, change SDA
		WriteByte((1|bit));
		WriteByte((1|bit));
		WriteByte((1|bit));//SCL = 1, hold SDA
		WriteByte((0|bit));
		WriteByte((0|bit));////SCL = 0, ready for next bit
	}
	WriteByte(0x02);
	WriteByte(0x02);//SCL = 0,SDA = 1
	flag = GetAck();//ACK READ,wait Client pull SDA to low
	WriteByte(0x03);
	WriteByte(0x03);//SCL = 1,SDA = 1
	WriteByte(0x02);
	WriteByte(0x02);//SCL = 0,SDA = 1
	return flag;
}

bool parallel::GetAck()
{
//Return true if ack ok
//ACK: client pull data line to low
	BYTE val;
	for(int i =0;i<10;i++){
	val = ReadByte();
//SDA in 0x0379 bit 4
	if ( (val&0x10) == 0 )
		return true;
	}
	return false;
}

BYTE parallel::ReceiveByte()
{
	//SDA == 1
	BYTE val = 0,tmp =0;
	for(int i=0;i<8;i++){
	WriteByte(0x02);//SCL = 0
	WriteByte(0x02);//SCL = 0
	WriteByte(0x03);//SCL = 1
	WriteByte(0x03);//SCL = 1
	tmp = ReadByte();
	tmp = (tmp & 0x10)>>4;
	val = val << 1;
	val += tmp;
	WriteByte(0x02);//SCL = 0
	}
	WriteByte(0x00);//SCL = 0,SDA =0 ,ACK
	WriteByte(0x00);//SCL = 0,SDA =0 ,ACK
	WriteByte(0x01);//SCL = 1
	WriteByte(0x01);//SCL = 1
	WriteByte(0x00);//SCL = 0
	WriteByte(0x02);//SCL = 0
	return val;
}

BYTE parallel::ReceiveByteNoAck()
{
	//SDA == 1
	BYTE val = 0,tmp =0;
	for(int i=0;i<8;i++){
	WriteByte(0x02);//SCL = 0
	WriteByte(0x02);//SCL = 0
	WriteByte(0x03);//SCL = 1
	WriteByte(0x03);//SCL = 1
	tmp = ReadByte();
	tmp = (tmp & 0x10)>>4;
	val = val << 1;
	val += tmp;
	WriteByte(0x02);//SCL = 0
	}
	WriteByte(0x02);//SCL = 0
	SendStop();
	return val;
}

bool parallel::CheckBus()
{
	if(!m_bBusy)
		m_bBusState=!GetAck();
	return m_bBusState;
}