电子电工课程设计(多功能数字时钟万历)

void write_onechar(unsigned char dat) {

unsigned char i=0; for(i=0;i<8;i++) {

DQ=0;

DQ=dat&0x01; delay0(15); DQ=1;

dat=dat>>=1; }

delay0(5); }

unsigned char read_onechar() {

unsigned char i=0;unsigned char dat=0; for(i=0;i<8;i++) {

DQ=0; dat>>=1; DQ=1;

if(DQ) dat|=0x80; delay0(20); }

return(dat); }

unsigned char Read_Temperature() {

unsigned char a,b;

unsigned char temp_value; init_ds18b20();

write_onechar(0xCC); //跳过读序列号的操作 write_onechar(0x44); // 启动温度转换 init_ds18b20();

write_onechar(0xCC); //跳过读序列号的操作

write_onechar(0xBE); //读取温度寄存器等（共可读9个寄存器） a=read_onechar(); b=read_onechar(); b=b<<4; a=a>>4; temp_value=b|a;

return(temp_value); }

前两个就是温度