The EEPROM, ADC and RTC will require an interface for communication between them. Due to that I2C bus is used as an interface between EPROM, ADC and RTC. It is used to minimize system-level interconnect. This simplifies the system level design and the design of the mother-board and associated chip-boards. The I2C protocol was given by Philips semiconductors in order to allow faster devices to communicate with slower devices and also allow devices to communicate with each other over a serial data bus without data loss. The authors designed home automation using I2C bus which makes it easier to implement it.