51单片机（入门）——DS18B20

目录

一、原理

二、单总线协议

三、编程

四、总结

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一、原理

如图：

原理图很简单，DQ与P14相接，通过单总线协议给P14传输信息，DS18B20（图中的U5）能够读出温度，传给P14

相关文献

The DS18B20 digital thermometer provides 9-bit to 12-bit Celsius temperature measurements and has an alarm function with nonvolatile userprogrammable upper and lower trigger points. The DS18B20 communicates over a 1-Wire bus that by definition requires only one data line (and ground) for communication with a central microprocessor. It has an operating temperature range of -55°C to +125°C and is accurate to ±0.5°C over the range of -10°C to +85°C. In addition, the DS18B20 can derive power directly from the data line (“parasite power”), eliminating the need for an external power supply. Each DS18B20 has a unique 64-bit serial code, which allows multiple DS18B20s to function on the same 1-Wire bus. Thus, it is simple to use one microprocessor to control many DS18B20s distributed over a large area. Applications that can benefit from this feature include HVAC environmental controls, temperature monitoring systems inside buildings, equipment, or machinery, and process monitoring and control systems.

可在手册中查询

其特点是

 Unique 1-Wire® Interface Requires Only One Port Pin for Communication