AVR单片机软件模拟I2C，读写24C1024(测试成功)

crazydtone · 发表于 2013-6-4 15:02:25

由于最近项目用到，特此传上来供童鞋们参考以及共同学习。

//imitate_i2c.h
#ifndef __IMITATE_I2C_H__
#define __IMITATE_I2C_H__

#include<iom64v.h>
#include<macros.h>
#include "TypeDefs.h"
#ifdef __IMITATE_I2C_C
#define IMITATE_I2C
#else
#define IMITATE_I2C extern
#endif

#define INPUT 0
#define OUTPUT 1
#define _BIT0 0x01 //0000 0001
#define  _nop_() asm("nop")

#define CHANGE_PIN_DIR(DDRX, BITX,STATUS) /*\
{ \
if(STATUS==0)\
{ \
DDRX&=~BIT(BITX);\
   } \
else if(STATUS==1)\
DDRX|=BIT(BITX);\
}*/

//control 24C1024 used port
#define _24C1024_DDR DDRG
#define _24C1024_PORT PORTG
#define _24C1024_PINX PING
#define OSCL 0
#define OSDA 1

#define _24C1024_I2C_PORT_INIT()    \
_24C1024_DDR&=~(BIT(OSCL)|BIT(OSDA));\
_24C1024_PORT&=~(BIT(OSCL)|BIT(OSDA))

#define OSCL_HIGH()    \
_24C1024_DDR&=~BIT(OSCL)

#define OSCL_LOW() \
_24C1024_DDR|=BIT(OSCL)

#define OSDA_HIGH() \
_24C1024_DDR&=~BIT(OSDA)

#define OSDA_LOW() \
_24C1024_DDR|=BIT(OSDA)

#define _LOW 0
#define _HIGH 1
#define FALSE 0
#define TRUE 1

/////////////////////////////////////////////
// I2C common definition
/////////////////////////////////////////////

#define  i2cSetSCL(is_hl)       \
{ \
if(is_hl==_HIGH)\
OSCL_HIGH();\
else \
OSCL_LOW();\
}

#define  i2cSetSDA(is_hl)      \
{ \
if(is_hl==_HIGH) \
OSDA_HIGH(); \
else \
OSDA_LOW(); \
}

#define i2cSCL_PIN_STATUS ((_24C1024_PINX&BIT(OSCL))>>OSCL)

#define i2cSDA_PIN_STATUS ((_24C1024_PINX&BIT(OSDA))>>OSDA)

// type definition
typedef enum _I2cIoTransType
{
I2C_TRANS_READ,
I2C_TRANS_WRITE
}I2cIoTransType;

#define I2C_DEVICE_ADR_WRITE(slave_adr) (slave_adr & ~_BIT0)
#define I2C_DEVICE_ADR_READ(slave_adr) (slave_adr | _BIT0)

#define I2C_ACCESS_DUMMY_TIME 3

#define I2C_ACKNOWLEDGE       _LOW
#define I2C_NON_ACKNOWLEDGE _HIGH

//===================================================================================//
//========================== For oprating 24C1024=========================================//
// for i2c
IMITATE_I2C void i2cSetSCL_Chk(BYTE bSet);
IMITATE_I2C void i2cSetSDA_Chk(BYTE bSet);
IMITATE_I2C BYTE i2c_Start(void);
IMITATE_I2C void i2c_Stop(void);
IMITATE_I2C BYTE i2c_ReceiveByte(BYTE bAck);
IMITATE_I2C BYTE i2c_SendByte(BYTE ucVal);
IMITATE_I2C BYTE i2c_AccessStart(BYTE ucSlaveAdr, I2cIoTransType trans_t);
IMITATE_I2C void i2cBurstReadBytes(BYTE ucSlaveAdr, UINT ucSubAdr, BYTE *pBuf, BYTE ucBufLen);
IMITATE_I2C void i2cBurstWriteBytes(BYTE ucSlaveAdr, UINT ucSubAdr, BYTE *pBuf, BYTE ucBufLen);
IMITATE_I2C BYTE i2cReadByte(BYTE ucSlaveAdr, UINT ucSubAdr);
IMITATE_I2C void i2cWriteByte(BYTE ucSlaveAdr, UINT ucSubAdr, BYTE ucVal);

#define MCU_XTAL_CLK_HZ 8000000

#define MCU_XTAL_CLK_KHZ (MCU_XTAL_CLK_HZ / 1000)
#define MCU_XTAL_CLK_MHZ (MCU_XTAL_CLK_KHZ / 1000)

///////////////////////////////////////
// MCU delay definition
///////////////////////////////////////
// 2(status sequence) * 6(S1-S6)
#define MCU_MACHINE_CYCLE 12 // unit: oscillatory cycle

// (MCU_MACHINE_CYCLE / 2) -> decimal fraction
#define MCU_MICROSECOND_NOP_NUM ((MCU_XTAL_CLK_MHZ + (MCU_MACHINE_CYCLE / 2)) / MCU_MACHINE_CYCLE)

#define I2C_CHECK_PIN_TIME 1000 // unit: 1 us
#define I2C_CHECK_PIN_CYCLE  8 // cycle of check pin loopp
#define I2C_CHECK_PIN_DUMMY  ((I2C_CHECK_PIN_TIME / I2C_CHECK_PIN_CYCLE) * MCU_MICROSECOND_NOP_NUM)

#if (MCU_MICROSECOND_NOP_NUM <= 1)
#undef MCU_MICROSECOND_NOP_NUM
#define MCU_MICROSECOND_NOP_NUM 1

#define MCU_Delay1us() \
      { \
      _nop_(); \
   }
#elif (MCU_MICROSECOND_NOP_NUM <= 2)
#define MCU_Delay1us() \
{ \
        _nop_(); \
        _nop_(); \
}
#elif (MCU_MICROSECOND_NOP_NUM <= 3)
#define MCU_Delay1us() \
{ \
      _nop_(); \
        _nop_(); \
        _nop_(); \
   }
#elif (MCU_MICROSECOND_NOP_NUM <= 4)
#define MCU_Delay1us() \
{ \
        _nop_(); \
      _nop_(); \
      _nop_(); \
      _nop_(); \
}
#elif (MCU_MICROSECOND_NOP_NUM <= 5)
#define MCU_Delay1us() \
{ \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
   }
#elif (MCU_MICROSECOND_NOP_NUM <= 6)
#define MCU_Delay1us() \
      { \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
      }
#elif (MCU_MICROSECOND_NOP_NUM <= 7)
#define MCU_Delay1us() \
      { \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
      }
#else
#define MCU_Delay1us() \
      { \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
         _nop_(); \
      }
#endif

#endif

// imitate_i2c.c

void i2c_Delay(void)
{
//MCU_Delay1us();
//MCU_Delay1us();
//MCU_Delay1us();
//MCU_Delay1us();
}

/////////////////////////////////////////
// Set I2C SCL pin high/low.
//
// Arguments: bSet - high/low bit
/////////////////////////////////////////
void i2cSetSCL_Chk(BYTE bSet)
{
BYTE ucDummy; // loop dummy

i2cSetSCL(bSet); // set SCL pin

if (bSet == _HIGH) // if set pin high
{
      ucDummy = I2C_CHECK_PIN_DUMMY; // initialize dummy
      CHANGE_PIN_DIR(_24C1024_DDR, OSCL, INPUT);
   asm("nop");
      while ((i2cSCL_PIN_STATUS == _LOW) && (ucDummy--)) ; // check SCL pull high
   CHANGE_PIN_DIR(_24C1024_DDR, OSCL, OUTPUT);
} // if
}

/////////////////////////////////////////
// Set I2C SDA pin high/low
//
// Arguments: bSet - high/low bit
/////////////////////////////////////////
void i2cSetSDA_Chk(BYTE bSet)
{
BYTE ucDummy; // loop dummy

i2cSetSDA(bSet);// set SDA pin

if (bSet == _HIGH) // if set pin high
{
      ucDummy = I2C_CHECK_PIN_DUMMY; // initialize dummy
      CHANGE_PIN_DIR(_24C1024_DDR, OSDA, INPUT);
   asm("nop");
      while ((i2cSDA_PIN_STATUS == _LOW) && (ucDummy--)) ; // check SDA pull high
      CHANGE_PIN_DIR(_24C1024_DDR, OSDA, OUTPUT);
} // if
}

//////////////////////////////////////////////////////
// I2C start signal.
// <comment>
//  SCL ________
//             \_________
//  SDA _____
//          \____________
//
// Return value: None
//////////////////////////////////////////////////////
BYTE i2c_Start(void)
{
BYTE bStatus = TRUE; // success status
i2cSetSDA_Chk(_HIGH);
i2c_Delay();
i2cSetSCL_Chk(_HIGH);
i2c_Delay();

// check pin error
CHANGE_PIN_DIR(_24C1024_DDR, OSCL, INPUT);
CHANGE_PIN_DIR(_24C1024_DDR, OSDA, INPUT);
asm("nop");asm("nop");asm("nop");
if ((i2cSCL_PIN_STATUS == _LOW) || (i2cSDA_PIN_STATUS == _LOW))
{
      CHANGE_PIN_DIR(_24C1024_DDR, OSCL, OUTPUT);
   CHANGE_PIN_DIR(_24C1024_DDR, OSDA, OUTPUT);
      bStatus = FALSE;
}
else // success
{
      CHANGE_PIN_DIR(_24C1024_DDR, OSCL, OUTPUT);
   CHANGE_PIN_DIR(_24C1024_DDR, OSDA, OUTPUT);
      asm("nop");asm("nop");asm("nop");
      i2cSetSDA(_LOW);
      i2c_Delay();
      i2cSetSCL(_LOW);
}
return bStatus;
}

/////////////////////////////////////////
// I2C stop signal.
// <comment>
//             ____________
//  SCL _______/
//                _________
//  SDA __________/
/////////////////////////////////////////
void i2c_Stop(void)
{
i2cSetSCL(_LOW);
i2c_Delay();
i2cSetSDA(_LOW);
i2c_Delay();
i2cSetSCL_Chk(_HIGH);
i2c_Delay();
i2cSetSDA_Chk(_HIGH);
i2c_Delay();
}

//////////////////////////////////////////////////////////////////////////
// I2C receive byte from device.
//
// Return value: receive byte
//////////////////////////////////////////////////////////////////////////
BYTE i2c_ReceiveByte(BYTE bAck)
{
BYTE ucReceive = 0;
BYTE ucMask = 0x80;
while(ucMask)
{
i2cSetSDA(_HIGH);
i2cSetSCL_Chk(_HIGH);
i2c_Delay();
        CHANGE_PIN_DIR(_24C1024_DDR, OSDA, INPUT);
asm("nop");
if(i2cSDA_PIN_STATUS == _HIGH)
ucReceive |= ucMask;
i2cSetSCL(_LOW);
i2c_Delay();
            ucMask >>= 1; // next
CHANGE_PIN_DIR(_24C1024_DDR, OSDA, OUTPUT);
asm("nop");
} // while

if (bAck) // acknowledge
      i2cSetSDA_Chk(I2C_ACKNOWLEDGE);
else // non-acknowledge
      i2cSetSDA_Chk(I2C_NON_ACKNOWLEDGE);

i2c_Delay();
i2cSetSCL_Chk(_HIGH);
i2c_Delay();
i2cSetSCL(_LOW);
i2c_Delay();
return ucReceive;
}

//////////////////////////////////////////////////////////////////////////
// I2C send byte to device.
//
// Arguments: ucVal - send byte
// Return value: I2C acknowledge bit
//             I2C_ACKNOWLEDGE/I2C_NON_ACKNOWLEDGE
//////////////////////////////////////////////////////////////////////////
BYTE i2c_SendByte(BYTE ucVal)
{
BYTE ucMask = 0x80;
BYTE    bAck; // acknowledge bit
while(ucMask)
{
      if (ucVal & ucMask)
         i2cSetSDA_Chk(_HIGH);
      else
         i2cSetSDA_Chk(_LOW);
      i2c_Delay();
      i2cSetSCL_Chk(_HIGH); // clock
      i2c_Delay();
      i2cSetSCL(_LOW);
      i2c_Delay();

      ucMask >>= 1; // next
} // while

// recieve acknowledge
i2cSetSDA(_HIGH);
i2c_Delay();
i2cSetSCL_Chk(_HIGH);
i2c_Delay();
CHANGE_PIN_DIR(_24C1024_DDR, OSDA, INPUT);
//_24C1024_PORT|=BIT(OSDA);
asm("nop");
bAck = i2cSDA_PIN_STATUS; // recieve acknowlege
i2cSetSCL(_LOW);
i2c_Delay();
CHANGE_PIN_DIR(_24C1024_DDR, OSDA, OUTPUT);
asm("nop");
return (bAck);
}

//////////////////////////////////////////////////////////////////////////
// I2C access start.
//
// Arguments: ucSlaveAdr - slave address
//          trans_t - I2C_TRANS_WRITE/I2C_TRANS_READ
//////////////////////////////////////////////////////////////////////////
BYTE i2c_AccessStart(BYTE ucSlaveAdr, I2cIoTransType trans_t)
{
BYTE ucDummy; // loop dummy

if (trans_t == I2C_TRANS_READ) // check i2c read or write
      ucSlaveAdr = I2C_DEVICE_ADR_READ(ucSlaveAdr); // read
else
      ucSlaveAdr = I2C_DEVICE_ADR_WRITE(ucSlaveAdr); // write

ucDummy = I2C_ACCESS_DUMMY_TIME;
while (ucDummy--)
{
      if (i2c_Start() == FALSE)
      {
         uart_send_str("\r\nNot getting start signal\r\n");
         continue;
      }

   //uart_send_str("\r\nAre you ok?\r\n");
      if (i2c_SendByte(ucSlaveAdr) == I2C_ACKNOWLEDGE) // check acknowledge
         return TRUE;

   uart_send_str("\r\n Not be ok!!  \r\n");
      i2c_Stop();

//       Delay1ms(1);
} // while

return FALSE;
}

/////////////////////////////////////////////////////////////////
// I2C read bytes from device.
//
// Arguments: ucSlaveAdr - slave address
//          ucSubAdr - sub address
//          pBuf - pointer of buffer
//          ucBufLen - length of buffer
/////////////////////////////////////////////////////////////////
void i2cBurstReadBytes(BYTE ucSlaveAdr, UINT ucSubAdr, BYTE *pBuf, BYTE ucBufLen)
{
BYTE ucDummy; // loop dummy

ucDummy = I2C_ACCESS_DUMMY_TIME;
while(ucDummy--)
{
      if (i2c_AccessStart(ucSlaveAdr, I2C_TRANS_WRITE) == FALSE)
         continue;

      if (i2c_SendByte(ucSubAdr>>8) == I2C_NON_ACKNOWLEDGE) // check non-acknowledge
         continue;

      if (i2c_SendByte(ucSubAdr&0xff) == I2C_NON_ACKNOWLEDGE) // check non-acknowledge
         continue;

      if (i2c_AccessStart(ucSlaveAdr, I2C_TRANS_READ) == FALSE)  // read i2c device must resend start signal
         continue;

      while(ucBufLen--) // loop to burst read
      {
         *pBuf = i2c_ReceiveByte(ucBufLen); // receive byte

         pBuf++; // next byte pointer
      } // while

      break;
} // while

i2c_Stop();
}

/////////////////////////////////////////////////////////////////
// I2C write bytes to device.
//
// Arguments: ucSlaveAdr - slave address
//          ucSubAdr - sub address
//          pBuf - pointer of buffer
//          ucBufLen - length of buffer
/////////////////////////////////////////////////////////////////
void i2cBurstWriteBytes(BYTE ucSlaveAdr, UINT ucSubAdr, BYTE *pBuf, BYTE ucBufLen)
{
BYTE ucDummy; // loop dummy

ucDummy = I2C_ACCESS_DUMMY_TIME;
while(ucDummy--)
{
      if (i2c_AccessStart(ucSlaveAdr, I2C_TRANS_WRITE) == FALSE)
      {
         uart_send_str("\r\nAccessstart failure\r\n");
         continue;
      }

      if (i2c_SendByte(ucSubAdr>>8) == I2C_NON_ACKNOWLEDGE) // check non-acknowledge
      {
         uart_send_str("\r\nSend High address failure\r\n");
         continue;
      }

      if (i2c_SendByte(ucSubAdr&0xff) == I2C_NON_ACKNOWLEDGE) // check non-acknowledge
      {
      uart_send_str("\r\nSend low address failure\r\n");
         continue;
      }
      while(ucBufLen--) // loop of writting data
      {
         i2c_SendByte(*pBuf); // send byte

         pBuf++; // next byte pointer
      } // while

      break;
} // while

i2c_Stop();
}

/////////////////////////////////////////////////////////////////
// I2C read a byte from device.
//
// Arguments: ucSlaveAdr - slave address
//          ucSubAdr - sub address
// Return value: read byte
/////////////////////////////////////////////////////////////////
BYTE i2cReadByte(BYTE ucSlaveAdr, UINT ucSubAdr)
{
BYTE ucBuf=0xFF; // byte buffer

i2cBurstReadBytes(ucSlaveAdr, ucSubAdr, &ucBuf, 1);
return ucBuf;
}

/////////////////////////////////////////////////////////////////
// I2C write a byte from device.
//
// Arguments: ucSlaveAdr - slave address
//          ucSubAdr - sub address
//          ucVal - write byte
/////////////////////////////////////////////////////////////////
void i2cWriteByte(BYTE ucSlaveAdr, UINT ucSubAdr, BYTE ucVal)
{
i2cBurstWriteBytes(ucSlaveAdr, ucSubAdr, &ucVal, 1);
}

// main.c

void main(void)
{
UINT index=0;
for(index=0;index<256;index++)
{
   i2cWriteByte(0xa0,index,index);
   Delay_nms(5);
}
            while(1)
{

for(index=0;index<256;index++)
{
uart_send_char(i2cReadByte(0xa0,index));
Delay_nms(100);
if(index==255)
while(1);
}
}
}

cdd329958 · 发表于 2013-8-2 14:24:09

高手写的就是不一样啊

yayagepei · 发表于 2013-12-13 14:54:34

收了，学习一下，谢楼主

liuzhen526 · 发表于 2013-12-13 15:18:47

mark i2c

laoqi777 · 发表于 2013-12-31 15:29:32

mark i2c

freethink168@ · 发表于 2014-1-2 16:42:25

mark i2c

hao999a · 发表于 2014-1-4 09:31:35

mark 正在学习AVR

weiwei4 · 发表于 2014-3-28 14:54:59

mark,标记下

Lauchael · 发表于 2014-4-2 18:55:33

Marking !!!

slzm40 · 发表于 2014-4-4 08:19:32

以前在51写的底层，然后移值到AVR昨晚调了一晚上不成功，刚好参考一下。谢谢

slzm40 · 发表于 2014-4-4 08:23:44

楼主写的风格和我很像啊。标准定义类型，看起来事办功倍。

wxty · 发表于 2014-4-6 22:27:56

木有注释。

puby · 发表于 2017-4-4 02:00:39

強帖留名，頂！

BS_good200xy · 发表于 2020-1-10 15:38:35

多谢分享，Mark!

elecfans123 · 发表于 2020-1-15 12:20:31

mark！iic速度还可以

AVR单片机软件模拟I2C，读写24C1024(测试成功)

阿莫论坛20周年了！感谢大家的支持与爱护！！