2440下的IIC实验

#include "2440addr.h"
extern void Uart_Printf(char *fmt,...);
void Wr24C02(U32 slvAddr,U32 addr,U8 data);
void Rd24C02(U32 slvAddr,U32 addr,U8 *data);
void Run_IicPoll(void);
void IicPoll(void) ;
void Delay(int x) ;
static U8 iicData[IICBUFSIZE];
static volatile int iicDataCount;
static volatile int iicStatus;
static volatile int iicMode;
static int iicPt;

void iicMain(void)
{
    unsigned int i,j;
    static U8 data[256];
    Uart_Printf("IIC Test(Polling) using AT24C02\n");
 
    //设置GPE15->IICSDA 和 GPE14->IICSCL
    rGPEUP  |= 0xc000;                  //Pull-up disable
    rGPECON &= ~0xf0000000;
    rGPECON |= 0xa0000000;              //GPE15:IICSDA , GPE14:IICSCL 
 
 //Enable ACK, Prescaler IICCLK=PCLK/16, Enable interrupt, Transmit clock value Tx clock=IICCLK/16
    rIICCON    = (1<<7) | (0<<6) | (1<<5) | (0xf);  //0xaf
    rIICADD  = 0x10;                    //2440 slave address = [7:1]
    rIICSTAT = 0x10;                     //IIC bus data output enable(Rx/Tx)
    Uart_Printf("Write test data into AT24C02\n");
   
 
//写入一个page的数据，page的大小是256byte，
    //page 的起始地址是0xa0，写入的数据是：0、1、2、...255。0xa0是AT24C02的页地址。
    //AT24C02的页地址是0x00/0x20/0x40/0x60/0x80/0xa0/0xc0/0xe0。
    for(i=0;i<256;i++)
       Wr24C02(0xa0,(U8)i,i);//U32 slvAddr,U32 addr,U8 data
      
      
    //初始化data数组的值为0。
    for(i=0;i<256;i++)
        data[i] = 0;
    Uart_Printf("Read test data from AT24C02\n");
    
    //读24C02的0xa0地址中数据到data数组中。
    for(i=0;i<256;i++)
        Rd24C02(0xa1,(U8)i,&(data[i])); 
    //输出data数组接收数据的值
    for(i=0;i<16;i++)
    {
        for(j=0;j<16;j++)
        Uart_Printf("%2x ",data[i*16+j]);
        Uart_Printf("\n");
    }
    Uart_Printf("OK! Write data is same to Read data!\n");
    while(1);
}

void Wr24C02(U32 slvAddr,U32 addr,U8 data)
{
    iicMode      = WRDATA;
    iicPt        = 0;
    iicData[0]   = (U8)addr;
    iicData[1]   = data;
    iicDataCount = 2;
    
    //8-bit data shift register for IIC-bus Tx/Rx operation.
    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    = 0xe0;//0xaf;     //Resumes IIC operation. //hzh
        while(iicStatus==0x100)  
            Run_IicPoll();
              
        if(!(iicStatus & 0x1))
            break;                      //When ACK is received
    }
    rIICSTAT = 0xd0;                     //Master Tx condition, Stop(Write), Output Enable
    rIICCON  = 0xe0;//0xaf;              //Resumes IIC operation.  //hzh
    Delay(1);                           //Wait until stop condtion is in effect.
      //Write is completed.
}

void Rd24C02(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)
        Run_IicPoll();
 
    iicMode      = RDDATA;
    iicPt        = 0;
    iicDataCount = 1;
    
    rIICDS   = slvAddr;
    rIICSTAT = 0xb0;                    //Master Rx,Start
    rIICCON  = 0xe0;//0xaf;              //Resumes IIC operation.  
    while(iicDataCount!=-1)
        Run_IicPoll();
 
    *data = iicData[1];
}

void Run_IicPoll(void)
{
    if(rIICCON & 0x10)                  //Tx/Rx Interrupt Enable
       IicPoll();
}

      
void IicPoll(void)
{
    U32 iicSt,i;
    iicSt = rIICSTAT; 
    if(iicSt & 0x8){};                   //When bus arbitration is failed. 总线仲裁失败
    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  = 0xc0；     
            Delay(1);                   //Wait until stop condtion is in effect. 
                                      
                                      
            break;    
        }      
        iicData[iicPt++] = rIICDS;
                    //The last data has to be read with no ack.
 if((iicDataCount)==0)
            rIICCON = 0x60;//0x2f;           
    else 
            rIICCON = 0xe0;//0xaf;     
        break;
                  
      case SETRDADDR:
          if((iicDataCount--)==0)
          {
              break;                       
          }
          rIICDS = iicData[iicPt++];
  for(i=0;i<10;i++);          
            rIICCON = 0xc0;              
            break;
            default:
            break;      
    }
}

void Delay(int x) 
 {
  int k,j;
  while(x)
  {
   for(k=0;k<=0xff;k++)
    for(j=0;j<=0xff;j++);
    x--;
  }