Arduino, an open source controller having ATMEGA 328 was used. I had unused PS2 mouse and keyboard, so decided to hack it. I used these to control my robot. The data sent by PS2 Mouse and keyboard was serially send to the controller and processing was done on the raw input data. The processed data was then used to move a robot. The standard PS2 mouse interface supports the following inputs: X (right/left) movement, Y (up/down) movement, left button, middle button, and right button. The mouse periodically reads these inputs and updates various counters and flags to reflect movement and button states. Similarly, PS2 keyboard also sends data in hexadecimal format which is interpreted by the controller.