51单片机-AT24C
加入技术交流群
void write(uchar date)
{
uchar i,temp;
temp=date;
for(i=0;i＜8;i++)
{
temp=temp＜＜1;
SCL=0;
delay();
SDA=CY;
delay();
SCL=1;
delay();
}
SCL=0;
delay();
SDA=1;
delay();
}
uchar read()
{
uchar i,k;
SCL=0;
delay();
SDA=1;
delay();
for(i=0;i＜8;i++)
{
SCL=1;
delay();
k=(k＜＜1)|SDA; // 将SDA赋给K的每一位
SCL=0;
delay();
}
return k;
}
void response(){
int i;
SCL = 1; //在SCL为高电平期间，进行应答
delay();
while((SDA == 1) && (i ＜ 170))i++; //SCL释放总线，等待从设备应答，从设备会把SDA拉低
SCL = 0;
delay();
}
void At24c_Write(uchar address, uchar value){
start();
write(0xa0); //写入设备地址
response();
write(address); //写入首地址
response();
write(value); //写入数据
response();
stop();
}
uchar At24c_Read(uchar address){
uchar value;
start();
write(0xa0); //伪写，先写入设备地址
response();
write(address); //再写入要读取数据的首地址
response();
start(); //再次
write(0xa1); //写入要读取数据的地址，方向为1
response();
value = read(); //读取数据
stop();
return value;
}
void main(){
uint i;
flag = 1;
P1 = 0x0; // 位选，使最地位数码管被选中
EA = 1;
ET0 = 1;
sum = 0;
temp = 0;
TMOD = 0x01;
TH0 = (65536 - 50000) / 256;
TL0 = (65536 - 50000) % 256;
TR0 = 1;
Init();
P2 = At24c_Read(23);
for(i = 0; i ＜ 10; i++)
if(duan[ i] == P2){
sum = i;
break;
flag = 0;
}
while(1){
if(temp == 20){
temp = 0;
if(sum == 10){
sum = 0;
}
if(flag == 1){
At24c_Write(23,duan[sum]);
delay1(100);
P2 = duan[sum];
}
sum++;
}
}
}
void time0() interrupt 1{
TH0 = (65536 - 50000) / 256;
TL0 = (65536 - 50000) % 256;
评论