DESIGNING OF AN EMBEDDED SYSTEM TO CONTROL THE TEMPERATURE OF POLYHOUSE

A temperature is one of the most important parameter for the proper growth and hence yields. From the survey it is found that most of the crop species has necessary optimum temperature range of 120C to 240C for proper growth. According to their optimum temperature the crops are cool season crops requiring temperature below 180C and warm season crops requiring temperature above 180C. It is necessary to provide the controlled temperature environment for crops those are growing in the Polyhouse. Therefore, AVR microcontroller based embedded system is designed to control the temperature of the Polyhouse environment depending on type of the crop and presented in this paper. The present embedded system is designed by using AVR ATmega32 Microcontroller and for the measurement of temperature the semiconductor sensor LM35 is used. The on chip ADC is implemented to convert the temperature dependent analog signal into the digital signal. To ensure the digital readout the smart LCD module is interfaced to microcontroller. The solid state relays are used to interface the heater and ventilator to control the Polyhouse environmental temperature. The firmware is developed in embedded C in Code Vision, IDE. The system is calibrated and standardized to the degree centigrade unit. The results regarding implementation of an embedded system are interpreted in this paper.