优龙S3C44B0X 的IIC驱动问题

swayz88

优龙S3C44B0X 的IIC驱动问题 [复制链接]

具体代码如下：
有时候读写的时候，特别是写EEPROM的时候出现死机，即 while(_iicDataCount!=-1);在这一句处循环，无法退出。
但是又不确定，有时候又是好的，请问不知道哪里错了，望高手不吝赐教！！

谢谢！
========================
========================
void Iic_initial(void)
{
pISR_IIC = (UINT32) IicInt; /* EEPROM 中断入口 */

// enable IRQ IIC
rINTMSK      &= (~BIT_IIC) ;

// initialize IIC module
rPCONF |= 0xa; //PF0:IICSCL, PF1:IICSDA
rPUPF |= 0x3; //pull-up disable

//Enable ACK generation, IICCLK=MCLK/16, Enable interrupt,IIC-Bus transmit clock prescaler (15+1)
//66000000hz/16/(15+1) = 257Khz (257812.5)
rIICCON = (1<<7) | (0<<6)| (1<<5) | (0xf);

rIICADD = 0x10;    // S3C44B0X slave address

rIICSTAT = 0x10; // 1=Enable Rx/Tx
}

void Wr24C040(UINT32 slvAddr,UINT32 addr,UINT8 data)
{
_iicMode=WRITE_DATA;
_iicPt=0;
_iicData[0]=(UINT8)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.
}

SINT32 Rd24C040(UINT32 slvAddr,UINT32 addr,UINT8 *data)
{
UINT32 timeout;

_iicMode=SETRDADDR;

_iicPt=0;
_iicData[0]=(UINT8)addr;
_iicDataCount=1;

rIICDS=slvAddr;
rIICSTAT=0xf0; //MasTx,Start
//Clearing the pending bit isn't needed because the pending bit has been cleared.

timeout = 0xffff ;
while(_iicDataCount!=-1)
{
if (timeout--  == 0)
{
return -1 ;
}
}

_iicMode=READ_DATA;

_iicPt=0;
_iicDataCount=1;

rIICDS=slvAddr;
rIICSTAT=0xb0; //MasRx,Start
rIICCON=0xaf;  //resumes IIC operation.

timeout = 0xffff ;
while(_iicDataCount!=-1)
{
if (timeout--  == 0)
{
return -1 ;
}
}

*data=_iicData[1];

return 0 ;
}

void __irq IicInt(void)
{
UINT32 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 READ_DATA:
      if((_iicDataCount--)==0)
      {
_iicData[_iicPt++]=rIICDS;

rIICSTAT=0x90;  //stop MasRx condition --> IIC-bus STOP signal generation
rIICCON=0xaf; //resumes IIC operation. --> Clear pending condition
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 WRITE_DATA:
      if((_iicDataCount--)==0)
      {
rIICSTAT=0xd0; //stop MasTx condition --> IIC-bus STOP signal generation
rIICCON=0xaf; //resumes IIC operation. --> Clear pending condition
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:
      //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;
}
}

tsz

_iicDataCount是怎么定义的？

yelanghijie

把它定义成 volatile int _iicDataCount试试。

lianyudandan

谢谢楼上两位的回答，
以下为宏定义和变量定义；

#define WRITE_DATA       (1)
#define POLLACK      (2)
#define READ_DATA       (3)
#define SETRDADDR    (4)

#define IICBUFSIZE 0x20

UINT8 _iicData[IICBUFSIZE];
volatile SINT32 _iicDataCount;
volatile SINT32 _iicStatus;
volatile SINT32 _iicMode;
SINT32 _iicPt;

LLL123

没仔细看你的代码，前面看到一个帖子，S3C好像从设备的地址需要右移一位。

rIICDS=slvAddr;//应该使用0xa0 >> 1;

试试看吧。

三生石

谢谢楼上的回家，下次试试看吧。

感觉奇怪的是，很多时候程序跑得很正常，就是偶尔出现错误；有时候出现的概率又比较大。所以肯定代码有问题，

运行不稳定呢。

但是基本的控制都是符合EEPROM的是需要求的呢。

不解呢？还望各位帮忙呢。…………

troy