Making Flowchart

Lesson 1: Video and Graphics Adapter 

1.1. Learning Objectives 
On completion of this lesson you will be able to describe:
 What is a microcomputer
 Different types of microcomputer.

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1.2. Introduction 

The PC, like most computers, uses video cathode ray tube (CRT) technology to display information for user reception. To allow the computer to communicate with a display monitor, a display adapter must be inserted in one of the PC's expansion slots. 

1.3. Different Types of Display Adapter 

The basic kind of video board you find in the PC world today is called the Video Graphics Array, or VGA. It can display information in a text-only form, or in a graphical form. For years, graphical standards were created by IBM, video boards with names like MDA, CGA, PGA, 8514, EGA, and VGA. But the lack of industry centralization has left us with no new standards; instead, there are a lot of video boards that exceed the capabilities of VGA boards, generically called "super VGA" boards. Even though they're all lumped under the name "super VGA," they’re all different. despite their variation.

1.4. How the Display Adapter Works 
Video boards all have several distinct components The video board contains video memory as you learned earlier in the discussion on memory. The CPU places the video image into the video memory. A video chip on the video board then examines the data in the video memory and creates a digital image signal. That digital signal is then converted to an analog signal by a chip called the DAC, the Digital-to-Analog Converter, another chip on the video board, and the resultant signal goes out the connector on the back of the board, and into your monitor.