2020年02月15日 | MSP430 IIC通信

#include

#define OP_READ 0xa1                    //器件地址读

#define OP_WRITE 0xa0                   //器件地址写

#define uchar unsigned char

#define uint unsigned int 

#define SDA_OUT P1DIR |= BIT3

#define SDA_IN P1DIR &= ~BIT3

#define SCL_OUT P1DIR |= BIT2

#define SCL_IN P1DIR &= ~BIT2

#define SDA_H P1OUT |= BIT3

#define SDA_L P1OUT &= ~BIT3

#define SCL_H P1OUT |= BIT2

#define SCL_L P1OUT &= ~BIT2

#define wei_h P5OUT |= BIT5

#define wei_l P5OUT &= BIT5

#define duan_l P6OUT &= ~BIT6

#define duan_h P6OUT |= BIT6

uchar table[16] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};

uchar miao;

uchar write;

int num;

void delayus(uint z)

{

  uint i,j;

  for(i = 0;i<20;i++)

    for(j=0;j    {;;};

}

void start()

{

  SDA_OUT;

  SCL_OUT;

  SDA_H;

  SCL_H;

  delayus(1);

  SDA_L;

  delayus(2);

  SCL_L;

}

void stop()

{

  SDA_OUT;

  SCL_OUT;

  SDA_L;

  delayus(2);

  SCL_H;

  delayus(2);

  SDA_H;

}

void Ack24()

{

  SDA_OUT;

  SCL_OUT;

  SDA_H;

  SCL_H;

  delayus(2);

  SDA_IN;

  while(P1IN & BIT3)

      SCL_L;

  delayus(2);

}

//mcu读取数据

uchar read_byte()

{

  uchar i,read_data;

  SDA_OUT;

  SCL_OUT;

  for(i = 0;i<8;i++)

  {

    SDA_H;

    delayus(1);

    SCL_H;

    SDA_IN;

    read_data <<= 1;

    if(P1IN & BIT3)

      read_data |= 0x01;

      SDA_OUT;

      SCL_L;   

  }

  return(read_data);

}

void write_byte(uint dat)

{

  uchar i;

  SDA_OUT;

  SCL_OUT;

  for(i = 0;i<8;i++)

  {

    if(dat&0x80)

      SDA_H;

    else

      SDA_L; 

    delayus(2);

    SCL_H;

    delayus(2);

    SCL_L;

    delayus(2);

    dat <<= 1;

  }

  SCL_L;

  delayus(2);

  SDA_H;

  delayus(2);

}

//向指定地址写数据

void write_dat(uchar addr,uchar write_data)

{

  SDA_OUT;

  SCL_OUT;

  SDA_H;

  SCL_H;

  start();

  write_byte(OP_WRITE);

  Ack24();

  write_byte(addr);

  Ack24();

  write_byte(write_data);

  Ack24();

  stop();

  delayus(1000);

}

//从指定地址读数据

uchar read_random(uint random_addr)

{

  uchar i;

  SDA_OUT;

  SCL_OUT;

  SDA_H;

  SCL_H;

  start();

  write_byte(OP_WRITE);

  Ack24();

  write_byte(random_addr);

  Ack24();

  start();

  write_byte(OP_READ);

  Ack24();

  i = read_byte();

  stop();

  return i;

}

void display(uchar dat)

{

  P4OUT = table[dat];

  duan_h;

  duan_l;

  P4OUT = ~(1 << num);

  wei_h;

  wei_l;

}

void Clock(void)

{

  miao++;

  if(miao==10)

    miao=0;

}

void main( void )

{

  P1DIR = 0XFF,P1OUT = 0XFF;

  P2DIR = 0XFF,P2OUT = 0XFF;

  P3DIR = 0XFF,P3OUT = 0XFF;

  P4DIR = 0XFF,P4OUT = 0XFF;

  P5DIR = 0XFF,P5OUT = 0XFF;

  P6DIR = 0XFF,P6OUT = 0XFF;

  SDA_OUT;

  SCL_OUT;

  SDA_H;

  SCL_L;

  // Stop watchdog timer to prevent time out reset

  WDTCTL = WDTPW + WDTHOLD;

  CCR0 = 32768 -1;

  TACTL = TASSEL_1 + MC_1;

  CCTL0 |= CCIE;

  _EINT();

  miao = read_random(3);

  if(miao>9) miao=0;

  while(1)

  {

    display(miao);

    if(write==1)

    {

      write = 0;

      write_dat(3,miao);

    }

    LPM3;

  }

}

#pragma vector = TIMERA0_VECTOR

__interrupt void TimerA_ISR(void)

{

  Clock();

  write = 1;

  LPM3_EXIT;

}