RELATIVE HUMIDITY AND AIR TEMPERATURE MICROCONTROLER-BASED DATA LOGGER DEVELOPMENT
Relative humidity (RH) and air temperature are important parameter in meteorological measurement. These two parameters should be measured continuously for fisheries and marine environmental monitoring. A data logger for this purpose need to be developed. The data logger consist of ATmega32 microcontroller run at 8Mhz clock, DS1307 Real-time Clock, Sensirion SHT11 sensor, SD card socket, Low-dropout Linear Regulator LP2950 and AIC1734. Light emitting diode and several passive components such as resistor and capacitor also needed. Data logger firmware was written in BASIC language using BASCOM-AVR version 184.108.40.206. The field test showed the greatest error in measure RH is -20,4% and air temperature is 7,3ºC. Measurement error is caused by contamination in sensor probe and lack of PCB design in releasing heat.