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基于51單片機(jī) 18b20仿真原理圖如下(proteus仿真工程文件可到本帖附件中下載)
單片機(jī)源程序如下(帶有詳細(xì)的注釋):
- #include<reg51.h>
- #include<lcd1602.h>
- #include<18b20.h>
- #define uchar unsigned char
- #define uint unsigned int
- bit flag1s = 0; //1s定時標(biāo)志
- unsigned char T0RH = 0; //T0重載值的高字節(jié)
- unsigned char T0RL = 0; //T0重載值的低字節(jié)
- void ConfigTimer0(unsigned int ms);
- unsigned char IntToString(unsigned char *str, int dat);
- extern bit Start18B20();
- extern bit Get18B20Temp(int *temp);
- extern void InitLcd1602();
- extern void LcdShowStr(unsigned char x, unsigned char y, unsigned char *str);
- void main()
- {
- bit res;
- int temp; //讀取到的當(dāng)前溫度值
- int intT, decT; //溫度值的整數(shù)和小數(shù)部分
- unsigned char len;
- unsigned char str[12];
- EA = 1; //開總中斷
- ConfigTimer0(10); //T0定時10ms
- Start18B20(); //啟動DS18B20
- InitLcd1602(); //初始化液晶
-
- while (1)
- {
- if (flag1s) //每秒更新一次溫度
- {
- flag1s = 0;
- res = Get18B20Temp(&temp); //讀取當(dāng)前溫度
- if (res) //讀取成功時,刷新當(dāng)前溫度顯示
- {
- intT = temp >> 4; //分離出溫度值整數(shù)部分
- decT = temp & 0xF; //分離出溫度值小數(shù)部分
- len = IntToString(str, intT); //整數(shù)部分轉(zhuǎn)換為字符串
- str[len++] = '.'; //添加小數(shù)點
- decT = (decT*10) / 16; //二進(jìn)制的小數(shù)部分轉(zhuǎn)換為1位十進(jìn)制位
- str[len++] = decT + '0'; //十進(jìn)制小數(shù)位再轉(zhuǎn)換為ASCII字符
- while (len < 6) //用空格補(bǔ)齊到6個字符長度
- {
- str[len++] = ' ';
- }
- str[len] = '\0'; //添加字符串結(jié)束符
- LcdShowStr(0, 0, str); //顯示到液晶屏上
- }
- else //讀取失敗時,提示錯誤信息
- {
- LcdShowStr(0, 0, "error!");
- }
- Start18B20(); //重新啟動下一次轉(zhuǎn)換
- }
- }
- }
- /* 整型數(shù)轉(zhuǎn)換為字符串,str-字符串指針,dat-待轉(zhuǎn)換數(shù),返回值-字符串長度 */
- unsigned char IntToString(unsigned char *str, int dat)
- {
- signed char i = 0;
- unsigned char len = 0;
- unsigned char buf[6];
-
- if (dat < 0) //如果為負(fù)數(shù),首先取絕對值,并在指針上添加負(fù)號
- {
- dat = -dat;
- *str++ = '-';
- len++;
- }
- do { //先轉(zhuǎn)換為低位在前的十進(jìn)制數(shù)組
- buf[i++] = dat % 10;
- dat /= 10;
- } while (dat > 0);
- len += i; //i最后的值就是有效字符的個數(shù)
- while (i-- > 0) //將數(shù)組值轉(zhuǎn)換為ASCII碼反向拷貝到接收指針上
- {
- *str++ = buf[i] + '0';
- }
- *str = '\0'; //添加字符串結(jié)束符
-
- return len; //返回字符串長度
- }
- /* 配置并啟動T0,ms-T0定時時間 */
- void ConfigTimer0(unsigned int ms)
- {
- unsigned long tmp; //臨時變量
-
- tmp = 11059200 / 12; //定時器計數(shù)頻率
- tmp = (tmp * ms) / 1000; //計算所需的計數(shù)值
- tmp = 65536 - tmp; //計算定時器重載值
- tmp = tmp + 2; //補(bǔ)償中斷響應(yīng)延時造成的誤差
- T0RH = (unsigned char)(tmp>>8); //定時器重載值拆分為高低字節(jié)
- T0RL = (unsigned char)tmp;
- TMOD &= 0xF0; //清零T0的控制位
- TMOD |= 0x01; //配置T0為模式1
- TH0 = T0RH; //加載T0重載值
- TL0 = T0RL;
- ET0 = 1; //使能T0中斷
- TR0 = 1; //啟動T0
- }
- ……………………
- …………限于本文篇幅 余下代碼請從51黑下載附件…………
復(fù)制代碼
所有資料51hei提供下載:
16.18b20.zip
(99.28 KB, 下載次數(shù): 133)
2017-12-26 11:57 上傳
點擊文件名下載附件
18b20
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