iic.c

S3C44b0X 的中断程序代码................

//44BTEST : iic.c
#include <string.h>
#include "..\inc\44b.h"
#include "..\inc\44blib.h"
#include "..\inc\def.h"
#include "..\inc\iic.h"
#define WRDATA (1)
#define POLLACK (2)
#define RDDATA (3)
#define SETRDADDR (4)
#define IICBUFSIZE 0x20
U8 _iicData[IICBUFSIZE];
volatile int _iicDataCount;
volatile int _iicStatus;
volatile int _iicMode;
int _iicPt;
void __irq IicInt(void);
void Test_Iic(void)
{
	unsigned int i,j,save_F,save_PF;
	static U8 data[256];
	Uart_Printf("[IIC Test using KS24C080]\n");
	save_F=rPCONF;
	save_PF=rPUPF;
	rPCONF |=0xa; //PF0:IICSCL, PF1:IICSDA
	rPUPF |=0x3; //pull-up disable
	pISR_IIC=(unsigned)IicInt;
	rINTMSK=~(BIT_GLOBAL|BIT_IIC);
	rIICCON=(1<<7)|(0<<6)|(1<<5)|(0xf);
	//Enable interrupt, IICCLK=MCLK/16, Enable ACK
	//40Mhz/16/(15+1) = 257Khz
	rIICADD=0x10; // S3C44B0X slave address
	rIICSTAT=0x10;
	Uart_Printf("Write test data into KS24C080\n");
	for(i=0;i<256;i++)
		Wr24C040(0xa0,(U8)i,i);
	for(i=0;i<256;i++)
		data[i]=0;
	Uart_Printf("Read test data from KS24C080\n");
	for(i=0;i<256;i++)
		Rd24C040(0xa0,(U8)i,&(data[i]));
	for(i=0;i<16;i++)
	{
		for(j=0;j<16;j++)
		Uart_Printf("%2x ",data[i*16+j]);
		Uart_Printf("\n");
	}
	rPCONF=save_F;
	rPUPF=save_PF;
}

void Wr24C040(U32 slvAddr,U32 addr,U8 data)
{
	_iicMode=WRDATA;
	_iicPt=0;
	_iicData[0]=(U8)addr;
	_iicData[1]=data;
	_iicDataCount=2;
	rIICDS=slvAddr;//0xa0
	rIICSTAT=0xf0; //MasTx,Start
	//Clearing the pending bit isn't needed because the pending bit has been cleared.
	while(_iicDataCount!=-1);
	_iicMode=POLLACK;
	while(1)
	{
		rIICDS=slvAddr;
		_iicStatus=0x100;
		rIICSTAT=0xf0; //MasTx,Start
		rIICCON=0xaf; //resumes IIC operation.
		while(_iicStatus==0x100);
		if(!(_iicStatus&0x1))
			break; // when ACK is received
	}
	rIICSTAT=0xd0; //stop MasTx condition
	rIICCON=0xaf; //resumes IIC operation.
	Delay(1); //wait until stop condtion is in effect.
	//write is completed.
}

void Rd24C040(U32 slvAddr,U32 addr,U8 *data)
{
	_iicMode=SETRDADDR;
	_iicPt=0;
	_iicData[0]=(U8)addr;
	_iicDataCount=1;
	rIICDS=slvAddr;
	rIICSTAT=0xf0; //MasTx,Start
	//Clearing the pending bit isn't needed because the pending bit has been cleared.
	while(_iicDataCount!=-1);
	_iicMode=RDDATA;
	_iicPt=0;
	_iicDataCount=1;
	rIICDS=slvAddr;
	rIICSTAT=0xb0; //MasRx,Start
	rIICCON=0xaf; //resumes IIC operation.
	while(_iicDataCount!=-1);
	*data=_iicData[1];
}
void __irq IicInt(void)
{
	U32 iicSt,i;
	rI_ISPC=BIT_IIC;
	iicSt=rIICSTAT;
	if(iicSt&0x8){} // when bus arbitration is failed.
	if(iicSt&0x4){} // when a slave address is matched with IICADD
	if(iicSt&0x2){} // when a slave address is 0000000b
	if(iicSt&0x1){} // when ACK isn't received
	switch(_iicMode)
	{
	case POLLACK:
		_iicStatus=iicSt;
		break;
	case RDDATA:
		if((_iicDataCount--)==0)
		{
		_iicData[_iicPt++]=rIICDS;
		rIICSTAT=0x90; //stop MasRx condition
		rIICCON=0xaf; //resumes IIC operation.
		Delay(1); //wait until stop condtion is in effect.
		//too long time...
		//The pending bit will not be set after issuing stop condition.
		break;
		}
		_iicData[_iicPt++]=rIICDS;
		//The last data has to be read with no ack.
		if((_iicDataCount)==0)
			rIICCON=0x2f; //resumes IIC operation with NOACK.
		else
			rIICCON=0xaf; //resumes IIC operation with ACK
		break;
	case WRDATA:
		if((_iicDataCount--)==0)
		{
			rIICSTAT=0xd0; //stop MasTx condition
			rIICCON=0xaf; //resumes IIC operation.
			Delay(1); //wait until stop condtion is in effect.
			//The pending bit will not be set after issuing stop condition.
			break;
		}
		rIICDS=_iicData[_iicPt++]; //_iicData[0] has dummy.
		for(i=0;i<10;i++); //for setup time until rising edge of IICSCL
		rIICCON=0xaf; //resumes IIC operation.
		break;
	case SETRDADDR:
	//Uart_Printf("[S%d]",_iicDataCount);
		if((_iicDataCount--)==0)
		{
			break; //IIC operation is stopped because of IICCON[4]
		}
		rIICDS=_iicData[_iicPt++];
		for(i=0;i<10;i++); //for setup time until rising edge of IICSCL
		rIICCON=0xaf; //resumes IIC operation.
		break;
	default:
		break;
	}
}