/********************************************************************/

/*******************I2C模拟通信及AT24C02底层驱动程序****************/

/********************************************************************/

//AT24C02

//delayus:延时约5us

void delayus()

{

;;

}

//i2c:initI2C总线初始化

void i2c_init()

{

SCL = 1;

delayus();

SDA = 1;

delayus();

}

//lcd:start 起始信号

void start()

{

SCL = 1;

SDA = 1;

delayus();

SDA = 0;

delayus();

}

//i2c:stop停止信号

void stop()

{

SCL = 1;

SDA = 0;

delayus();

SDA = 1;

delayus();

}

//i2c:ack从机应答信号

void ack()

{

uchar i = 0;

//在SCL = 1时，读取SDA的数据判忙

SCL = 1;

delayus();

while((SDA == 1)&& i < 250)

i++;

//判忙之后，等待发送数据/命令

SCL = 0;

delayus();

}

//nack:主机非应答信号

void nack()

{

//主机发送非应答信号1

SCL = 1;

delayus();

SDA = 1;

delayus();

//等待发送数据/命令

SCL = 0;

delayus();

}

//write:byte写一个字节数据

void write_byte(uchar date)

{//从最高位发送

uchar i, temp;

temp = date;

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

{

temp <<= 1;

SCL = 0;

delayus();

SDA = CY;

delayus();

SCL = 1;

delayus();

SCL = 0;

delayus();

}

//等待从机应答

SCL = 0;

delayus();

SDA = 1;//置1,等待从机应答0

delayus();

}

//read:byte 读一个字节数据

uchar read_byte()

{

uchar i, j, k;

SCL = 0;

delayus();

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

{

SCL = 1;

delayus();

j = SDA;

k = (k << 1) | j;

delayus();

SCL = 0;

delayus();

}

delayus();

return (k);

}

//write:AT24C02 写AT24C02

void write_c02(uchar address, uchar date)

{

start();

write_byte(write_add);

ack();

write_byte(address);

ack();

write_byte(date);

ack();

stop();

delay(12);

}

//read:AT24C02读AT24C02

uchar read_c02(uchar add)

{

uchar date = 0;

start();

write_byte(write_add);

ack();

write_byte(add);

ack();

start();

write_byte(read_add);

ack();

date = read_byte();

nack();

return (date);

}

//display:数码管显示程序

void display(uchar num)

{

uchar bai, shi, ge;

bai = num / 100 % 10;

shi = num / 10 % 10;

ge = num % 10;本文引用地址：http://www.eepw.com.cn/article/201612/324620.htm

dula = 1;

P0 = table[bai];

dula = 0;

P0 = 0xff;

wela = 1;

P0 = 0xfe;

wela = 0;

P0 = 0x00;

delay(1);

dula = 1;

P0 = table[shi];

dula = 0;

P0 = 0xff;

wela = 1;

P0 = 0xfd;

wela = 0;

P0 = 0x00;

delay(1);

dula = 1;

P0 = table[ge];

dula = 0;

P0 = 0xff;

wela = 1;

P0 = 0xfb;

wela = 0;

P0 = 0x00;

delay(1);

}

/********************************************************************/

/*************************UART串口通信******************************/

/********************************************************************/

//uart:initUART初始化

void uart_init()

{

TMOD = 0x20;

TH1 = 0xFD; //9600bps/s

TL1 = 0xFD;

TR1 = 1;

SM0 = 0;

SM1 = 1;

REN = 1;

EA = 1;

ES = 1;

}

//main:主程序

void main(void)

{

i2c_init();

lcd_init();

uart_init();

//LCD1602

write_cmd(0x80);

send_string(string_1);

write_cmd(0x80 + 0x40);

send_string(string_2);

//AT24C02

write_c02(0x0a, 0xaa);

num = read_c02(0x0a);

while(1)

{

display(num);

if(flag == 1)

{

ES = 0;

SBUF = num;

while(!TI);

TI = 0;

flag = 0;

ES = 1;

}

}

}

//UART:INT 串口中断程序

void uart_int() interrupt 4

{

RI = 0;

num = SBUF;

flag= 1;

}