iic.c

ARM S3C2410处理器 iic总线驱动程序 开发环境：ads1.2

/*
*********************************************************
* Copyright (c)
* All rights reserved.				            
*
* 文件名称：iic.c
* 文件标识：
* 摘    要：S3C2410 IIC-bus Master Tx/Rx mode Test Program
*             (Interrupt / Non Interrupt (Polling))
* 当前版本：1.0
* 作    者：刘征
* 完成日期：2005.4.3
*
* 取代版本：
* 作    者：
* 完成日期：
*********************************************************
*/

/*
*********************************************************
*   					 头文件
*********************************************************
*/
#include <string.h>
#include "2410addr.h"
#include "2410lib.h"
#include "def.h"
#include "iic.h"

/*
*********************************************************
*  					  变量
*********************************************************
*/
static U8 _iicData[IICBUFSIZE];
static volatile int _iicDataCount;
static volatile int _iicStatus;
static volatile int _iicMode;
static int _iicPt;

//===================================================================
//       S3c2410 IIC configuration
//  GPE15=IICSDA, GPE14=IICSCL
//  "Interrupt mode" for IIC block
//=================================================================== 
/*
*********************************************************
* 函数介绍：本函数是测试iic使用中断的程序。				
* 输入参数：无
* 输出参数：无
* 返回值  ：无
*********************************************************
*/
void Test_Iic(void)
{
    unsigned int i,j,save_E,save_PE;
    static U8 data[256];

    Uart_Printf("[ IIC Test(Interrupt) using KS24C080 ]\n");

    save_E   = rGPECON;
    save_PE  = rGPEUP;
    rGPEUP  |= 0xc000;                  //Pull-up disable
    rGPECON |= 0xa00000;                //GPE15:IICSDA , GPE14:IICSCL 

    pISR_IIC = (unsigned)IicInt;//设置中断处理函数入口
    rINTMSK &= ~(BIT_IIC);

    //Enable ACK, Prescaler IICCLK=PCLK/16, Enable interrupt, Transmit clock value Tx clock=IICCLK/16
    // If PCLK 50.7MHz, IICCLK = 3.17MHz, Tx Clock = 0.198MHz
    rIICCON = (1<<7) | (0<<6) | (1<<5) | (0xf);

    rIICADD  = 0x10;                    //2410 slave address = [7:1]
    rIICSTAT = 0x10;                    //IIC bus data output enable(Rx/Tx)

    Uart_Printf("Write test data into KS24C080\n");

    for(i=0;i<256;i++)
    {
    	Delay(1500);//延迟的目的是为了能充分表现中断的产生
        Wr24C080(0xa0,(U8)i,i);//写入数据
    }
           
    for(i=0;i<256;i++)
        data[i] = 0;

    Uart_Printf("Read test data from KS24C080\n");
    
    for(i=0;i<256;i++)
        Rd24C080(0xa0,(U8)i,&(data[i])); //读出数据

        //Line changed 0 ~ f
    for(i=0;i<16;i++)
    {
        for(j=0;j<16;j++)
            Uart_Printf("%2x ",data[i*16+j]);
        Uart_Printf("\n");
    }
    rINTMSK |= BIT_IIC;    
    rGPEUP  = save_PE;
    rGPECON = save_E;
}

/*
*********************************************************
* 函数介绍：本函数是iic写程序，将数据写入KS24C080（IIC EEPROM）。				
* 输入参数：slvAddr--基地址（0XA0）
*           addr--地址偏移量
*           data--写入的数据
* 输出参数：无
* 返回值  ：无
*********************************************************
*/
void Wr24C080(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);//_iicDataCount在中断处理程序里被减减

    _iicMode = POLLACK;//得到ACK

    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.
}
        
/*
*********************************************************
* 函数介绍：本函数是iic读程序，将数据从KS24C080（IIC EEPROM）读出。				
* 输入参数：slvAddr--基地址（0XA0）
*           addr--地址偏移量
*           *data--读出数据放入的BUF的首地址
* 输出参数：无
* 返回值  ：无
*********************************************************
*/
void Rd24C080(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];
}


/*
*********************************************************
* 函数介绍：本函数是iic中断处理程序。				
* 输入参数：无
* 输出参数：无
* 返回值  ：无
*********************************************************
*/
void __irq IicInt(void)
{
    U32 iicSt,i;
    
    rSRCPND = BIT_IIC;          //Clear pending bit
    rINTPND = 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:
            Uart_Printf("iic __irq WRDATA happen!\n");
            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