数字温度传感器DS18B20读出数据错误分析

为了在超声波液位测量仪中准确地测定环境温度,采用了单总线数字温度传感器DS18B20.针对单片机在读出DS18B20中数据时常出现错误的问题,从DS18B20的读出数据时序入手,分析了测量程序,特别是读出DS18B20的程序,发现了读出错误的原因,在KeilC单片机集成开发环境中,通过实验反复比较证实了所作的分析,也提出解决了这一问题的方法.实际应用表明,修改单片机读出DS18B20程序后,从未出现此问题.

Error Analyzing of Read-out Data of 1-wire Bus Digital Temperature Sensor DS18B20

For the purpose of accurately detecting the environment temperature in ultrasonic oil-level meter, the 1-wire bus digital temperature sensor DS18B20 was applied in the system. Aimed at the problem of reading error when MCU read DS18B20, by analyzing the timing of DS18B20 when reading, the detecting program, especially the reading out program is analyzed,by which the causes of reading out error is discovered. In the IDE of Keil C, the analysis is approved by many times experiment, and also the method of how to solve this problem is put forward. The practice application indicates that the error has never taken place after amending the program of reading DS18B20.