In this paper we describe about designing and development of I2C driver for ARM9 evaluation board running Linux specifically, attention is given to understand the i2c protocol by running a RTC application where master driver namely I2C-S3C2440.C and slave driver namely i2c.dev generic slave driver is used. I2c is an interface between processor and devices. It is a simple and low bandwidth protocol which allows for short distance on board communication, while being extremely modest in its hardware resource requirements. The intended out-come of this work is to give a contribution in under-standing how to access I2C devices on any Linux based embedded systems.