2019年04月02日 | STM32 IO 模拟IIC I2C

#define I2C_Speed        100000

#define I2C_EE             I2C1

#define uStatus0x80

#definedTime 5

#define I2C_EE_GPIO   GPIOB

#define I2C_EE_SCL         GPIO_Pin_5

#define I2C_EE_SDA         GPIO_Pin_4

#define I2C_EE_CLK         RCC_APB1Periph_I2C1

#define SCL_H         GPIOB->BSRR = GPIO_Pin_5

#define SCL_L         GPIOB->BRR  = GPIO_Pin_5

#define SDA_H         GPIOB->BSRR = GPIO_Pin_4

#define SDA_L         GPIOB->BRR  = GPIO_Pin_4

#define SCL_read      GPIOB->IDR  & GPIO_Pin_5

#define SDA_read      GPIOB->IDR  & GPIO_Pin_4

static unsigned int cntForInitial = 0;

static unsigned char fSigStatus = 0;

//static bool LedStatus = true;

void I2C_Init()

{

GPIO_InitTypeDef  GPIO_InitStructure;

    //* Configure I2C_EE pins: SCL and SDA

  GPIO_InitStructure.GPIO_Pin =  I2C_EE_SCL | I2C_EE_SDA;

  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //GPIO_Speed_50MHz;

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_OD;

  GPIO_Init(I2C_EE_GPIO, &GPIO_InitStructure);

}

static void i2c_start()

{

 SDA_H;

 SCL_H;

 DelayUs(dTime);

 SDA_L;

 DelayUs(dTime);

 SCL_L;

 DelayUs(dTime);

 //LedStatus = !LedStatus;

 //f_LCT1(LedStatus);

}

/*

******************************************************************

Fuction:

Stop i2c

******************************************************************

*/

static void i2c_stop()

{

    SDA_L;

 SCL_H;

 DelayUs(dTime);

 SDA_H;

 DelayUs(dTime);

 SCL_H;

 DelayUs(dTime);

}

/*

******************************************************************

Fuction:

i2c  Master wait for ack

Only ack

******************************************************************

*/

static unsigned char i2c_rd_ack()

{

    unsigned char flag = 0;

    SDA_H;

 SCL_H;

 DelayUs(dTime/2);

 flag = SDA_read;

 DelayUs(dTime/2);

 SCL_L;

 DelayUs(dTime/2);

 if(flag == 1)

 return 0;

 return 1;

}

/*

******************************************************************

Fuction:

i2c  Byte transmission

Only Send,no ack,no stop

******************************************************************

*/

static unsigned char i2c_sb(unsigned char Byte)

{

unsigned char cnt;

SCL_L;

for(cnt=0;cnt<8;cnt++)

{

  if(Byte&0x80)

   SDA_H;

   else

   SDA_L;

   DelayUs(dTime);

   SCL_H;

   DelayUs(dTime);

   SCL_L;

   Byte <<= 1;

   DelayUs(dTime);

}

return i2c_rd_ack();

}

/*

******************************************************************

Fuction:

i2c Byte receive

Return Byte

******************************************************************

*/

static unsigned char i2c_rb()

{

unsigned char cnt;

unsigned char Byte=0;

SDA_H;

    for(cnt=0;cnt<8;++cnt)

      {

Byte <<= 1;

DelayUs(dTime);

SCL_H;

DelayUs(dTime);

if(SDA_read)

Byte |= 0x01;

SCL_L;

DelayUs(dTime);

      }

    return Byte;

}

/*

******************************************************************

Fuction:

i2c ACK  Master send

******************************************************************

*/

static void i2c_wr_ack(unsigned char ACK)

{

  if(ACK)

SDA_H;

else

SDA_L;

 SCL_H;

 DelayUs(dTime);

 SCL_L;

 DelayUs(dTime);

}

/*

******************************************************************

Fuction:

i2c Byte receive

Return Byte

******************************************************************

*/

uint8_t ReadReg(unsigned int addr)

{

    uint8_t temp;

i2c_start();

if(!i2c_sb(BRG_DEV_ADDR))

{

i2c_stop();

return 0;

}

if(!i2c_sb((uint8_t)(addr >> 8)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((uint8_t)(addr & 0xFF)))

{

i2c_stop();

return 0;

}

i2c_start();

if(!i2c_sb(BRG_DEV_ADDR |0x01))

{

i2c_stop();

return 0;

}

temp = i2c_rb();

i2c_wr_ack(1);

i2c_stop();

return temp;

}

unsigned char WriteReg8(unsigned int addr,unsigned char wData)

{

i2c_start();

if(!i2c_sb(BRG_DEV_ADDR))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(addr >> 8)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(addr & 0xFF)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(wData)))

{

i2c_stop();

return 0;

}

i2c_stop();

//DelayUs(1);

return 1;

}

unsigned char WriteReg16(unsigned int addr,unsigned char wData1,unsigned char wData2)

{

i2c_start();

if(!i2c_sb(BRG_DEV_ADDR))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(addr >> 8)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(addr & 0xFF)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(wData2)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(wData1)))

{

i2c_stop();

return 0;

}

i2c_stop();

DelayUs(1);

return 1;

}

unsigned char WriteReg32(unsigned int addr,unsigned char wData1,unsigned char wData2,unsigned char wData3,unsigned char wData4)

{

i2c_start();

if(!i2c_sb(BRG_DEV_ADDR))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(addr >> 8)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(addr & 0xFF)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(wData4)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(wData3)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(wData2)))

{

i2c_stop();

return 0;

}

if(!i2c_sb((unsigned char)(wData1)))

{

i2c_stop();

return 0;

}

i2c_stop();

DelayUs(1);

return 1;

}