摘要
介绍了一款以MSP430F4250单片机为核心的温湿度变送器，在测量温度和湿度时，可同步将测量值变送为2路0～5V的电压输出，也可选择将测量值通过RS-485总线的方式进行传送。为了适应工业现场高温、高湿的测量要求，系统采用电容式湿度传感器，直流24V外部电源，充分利用MCU内部的D／A和定时器模块资源，采用MODBUS总线协议，结构简单，精度高、效果好。
This paper introduced a kind of humiture transducer＇ s design. It can measure temperature and humidity synchronized with two channels analog from 0 V to 5 V output or optionally digital RS - 485 output. The design was based on the MSP430F4250 single chip microcomputer;adopt capacitive humidity sensor for measuring high humidity of high temperature in industrial actuality; the external power was DC 24 V which used in workshop commonly ; the part of voltage output took use of D/A u- nit and timer-A unit that MCU integrated, auxiliary by the voltage processing circuit;and RS -485 bus adopted MODBUS protocol. The paper analyzed the details which from the overall hardware and software architecture request by the humiture transducer＇ s de- sign. The test result show that each parameter has achieved the design requirements, and it simplifies the hardware circuit, makes construction more compact and reduced the production cost.
出处
《仪表技术与传感器》
CSCD
北大核心
2010年第2期18-21,共4页
Instrument Technique and Sensor
