Abstract
This paper-based microcontroller design temperature and humidity control system, the completion of the system of temperature, humidity detection, control and display. Selection AT89C2051 control chip microcontroller, the main AD590 temperature sensor to detect temperature and humidity sensors used to detect HS1101 humidity, with the three control buttons to achieve key control, with eight LED control drive MAX7219 chip to complete the display part, with 8 Serial control of the ADC TLC0834 to complete the conversion of the chip. Data acquisition is part of temperature and humidity sensors will be placed in the internal flue-cured tobacco, measured temperature and humidity inside the flue-cured tobacco value, after the data into a digital signal conditioning into the AT89C2051 after the SCM, and then LED display to temperature and humidity measurements. SCM will default and to compare measurements, to make judgments based on the results, after analysis of treatment procedures accordingly sent instructions control executive body movements, or connected to the closure of various implementing agencies of the relay, which control nearly stove and into the throttle Mechanical wind tunnel opened the door to the size, Yici to regulate tobacco room temperature and humidity. This cycle so that the temperature and humidity values consistent with the settings. When the temperature and humidity of over allowed range of error, the system will issue a warning, if necessary, according to tobacco growers can be baked through the button to the extent of on-chip memory to amend the baking temperature and humidity default. Through the system as a whole the core part of the microcontroller design, to achieve optimal
of all details. Control algorithms using PID control.This design is easy to realize with MCU control temperature and humidity testing。
Key words: AT89C2051; PID algorithm; temperature and humidity