📄 iic.c
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#include <string.h>
#include "2410addr.h"
#include "IIC.h"
//===================================================================
// S3C2410 IIC configuration
// GPE15=IICSDA, GPE14=IICSCL
// Non-Interrupt mode for IIC block
//===================================================================
void IIC_write(unsigned int addr ,unsigned char data)
{
unsigned int save_E,save_PE;
// unsigned int save_MPLLCON;
// save_MPLLCON = rMPLLCON;
// rMPLLCON = 0xa1033;
save_E = rGPECON;
save_PE = rGPEUP;
rGPEUP |= 0xc000; //Pull-up disable
rGPECON = (rGPECON|0xf0000000)&0xafffffff; //GPE15:IICSDA , GPE14:IICSCL
//Enable ACK, Prescaler IICCLK=PCLK/512, Enable interrupt, Transmit clock value Tx clock=IICCLK/16
//24C02N 1.8-5.5V 100KHZ--400kHZ
//PCLK=50.7MHZ IICCLK=50.7/512=99KHZ
rIICCON = (1<<7) | (0<<6) | (1<<5) | (0xf);//0xef
rIICADD = 0xa0;
rIICSTAT = 0x10; //IIC bus data output enable(Tx/Rx)
Wr24C02(0xa0,addr,data);
rGPEUP = save_PE;
rGPECON = save_E;
// rMPLLCON = save_MPLLCON;
}
void IIC_read(unsigned int addr ,unsigned char* pdata)
{
unsigned int save_E,save_PE;
// unsigned int save_MPLLCON;
// save_MPLLCON = rMPLLCON;
// rMPLLCON = 0xa1033;
save_E = rGPECON;
save_PE = rGPEUP;
rGPEUP |= 0xc000; //Pull-up disable
rGPECON = (rGPECON|0xf0000000)&0xafffffff; //GPE15:IICSDA , GPE14:IICSCL
//Enable ACK, Prescaler IICCLK=PCLK/512, Enable interrupt, Transmit clock value Tx clock=IICCLK/16
//24C02N 1.8-5.5V 100KHZ--400kHZ
//PCLK=50.7MHZ IICCLK=50.7/512=99KHZ
rIICCON = (1<<7) | (0<<6) | (1<<5) | (0xf);//0xef
rIICADD = 0xa0;
rIICSTAT = 0x10; //IIC bus data output enable(Tx/Rx)
Rd24C02(0xa0,addr,pdata);
rGPEUP = save_PE;
rGPECON = save_E;
// rMPLLCON = save_MPLLCON;
}
//**********************[ DelayTime ]**************************************
void DelayTime(int time)
{
int i;
for(i=0;i<1000;i++);
return;
}
//*******************************************************************
//**************[ Wr24C02]*****************************************
void Wr24C02(unsigned int slvAddr,unsigned int addr,unsigned char data)
{
_iicMode = WRDATA;
_iicPt = 0;
_iicData[0] = (unsigned char)addr;
_iicData[1] = data;
_iicDataCount = 2;
rIICDS = slvAddr; //0xa0
//Master Tx mode, Start(Write), IIC-bus data output enable
//Bus arbitration sucessful, Address as slave status flag Cleared,
//Address zero status flag cleared, Last received bit is 0
rIICSTAT = 0xf0;
//Clearing the pending bit isn't needed because the pending bit has been cleared.
while(_iicDataCount!=-1)
Run_IicPoll();
_iicMode = POLLACK;
while(1)
{
rIICDS = slvAddr;
_iicStatus = 0x100; //To check if _iicStatus is changed
rIICSTAT = 0xf0; //Master Tx, Start, Output Enable, Sucessful, Cleared, Cleared, 0
rIICCON = 0xaf; //Resumes IIC operation.
while(_iicStatus==0x100)
Run_IicPoll();
if(!(_iicStatus & 0x1))
break; //When ACK is received
}
rIICSTAT = 0xd0; //Master Tx condition, Stop(Write), Output Enable
rIICCON = 0xaf; //Resumes IIC operation.
DelayTime(1); //Wait until stop condtion is in effect.
//Write is completed.
}
//************************[ Rd24C02]********************************
void Rd24C02(unsigned int slvAddr,unsigned int addr,unsigned char *data)
{
_iicMode = SETRDADDR;
_iicPt = 0;
_iicData[0] = (unsigned char)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)
Run_IicPoll();
_iicMode = RDDATA;
_iicPt = 0;
_iicDataCount = 1;
rIICDS = slvAddr;
rIICSTAT = 0xb0; //Master Rx,Start
rIICCON = 0xaf; //Resumes IIC operation.
while(_iicDataCount!=-1)
Run_IicPoll();
*data = _iicData[1];
}
//**********************[Run_IicPoll]**************************************
void Run_IicPoll(void)
{
if(rIICCON & 0x10) //Tx/Rx Interrupt Enable
IicPoll();
}
//**********************[IicPoll ]**************************************
void IicPoll(void)
{
unsigned int iicSt,i;
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.
DelayTime(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.
DelayTime(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:
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;
}
}
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