The second board of the data acquisition system is the Arduino board, which is a low cost microcontroller development board from Arduino Company. This board has been utilized to measure and to store the sensors data on the SD card in CSV file formats. The main component of the board is ATMega2560, which it is a powerful low cost microcontroller from ATMEL Company [26]. This microcontroller has a large memory size (256 KB program and 8 KB data memory) making it the most suitable microcontroller for the filing system and the SD cards applications. The microcontroller ATMega2560 is connected to the SD card via the SPI protocol as shown in Fig. 2.