Multimedia

Multimedia technology is growing faster in all fields. Multimedia effectively deals the computer-controlled integration of text, graphics, drawings, still and video images, animation and audio information. For creating a text file, word processing software like Microsoft Word is used. These text files are then imported to multimedia tools to integrate with other multimedia elements. Graphic is a generic term used often to describe the pictorial representation of data. Keyboard, mouse and trackball are graphic input devices. Graphic images can be modified by using software like Adobe Photoshop, Freehand and Corel Draw. The five methods of graphics are background, 2D graphics, 3D graphics, flowcharts and charts and graphs. Vibration of air molecules which can be sensed by human ear is audio. Transmission of mechanical vibration by an elastic medium is included in audio. Video comprises of moving picture accompanied by sound.  Animation is the process of sequencing still images in rapid succession to the effect of live motion.

Bus Interface Unit (BIU)

Microprocessors are now extensively used in many applications. A microprocessor consists of a central processing unit (CPU), memory, input devices and output devices. For the interconnection of these components, buses are used. A bus is a group of parallel lines which carries digital information between digital devices in a system. There exist three varieties here – address bus, data bus and control bus. Control bus is composed of various control lines. Data bus is used for sending information between microprocessor and memory or input/output devices (bidirectional). Address bus is used for sending information from microprocessor to memory or input/output devices (unidirectional).  Memory can be either RAM or ROM. Different input/output devices used here are keyboard, mouse, modem, ADC, DAC, monitor, printer etc. Bus interface unit (BIU) handles all bus operations. BIU generally contains first in first out registers of size 6 bytes in length called queue. BIU performs prefetching of instructions from memory and then stores these instructions in the queue. This process is termed as pipelining which increases the speed of microprocessors.