To move the cursor position 3 to draw graphics and

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: to I/O capabilities. It has local data editing capability and the ability to consolidate input data prior to sending them to the CPU of the main computer. This means that preliminary processing of input data can take place locally and that the data can be cleaned up at the terminal itself before it is transmitted to the main computer for processing this can lead to tremendous saving of clean data preparation time as compared to dumb terminals. However, smart terminals cannot be programmed by users. An intelligent terminal is a small computer by itself. It consists of a built-in microcomputer that can be programmed by users. These programmable terminals have extensive local data processing power. Large working files can be maintained locally and small data processing jobs can be handled by the terminal itself without the need to interact with the CPU of the main computer. They have their own on-line secondary storage devices like disk, which are used during the processing of these small jobs. Programmed error-detection tests can also be stored in the terminal for the validation of input data which can ensure the transmission of clean data to the main computer system for further processing. With the fast reduction in the cost of microcomputer components and disk storage, most terminals of today are intelligent or at least smart to help make data entry and retrieval easier for the users. X Terminals An X terminal is a graphics terminal that has a rich set of commands for the following: 1. To display characters. 2. To move the cursor position. 3. To draw graphics and images such as draw a line of desired thickness and color, draw an empty circle or a circle filled with a certain color, draw a bitmap, draw text, etc. 4. To manage areas on the screen (called windows) such as open a new window of the desired size, close an existing window, resize an existing window, etc. X terminals are very common these days. Terminal Emulators Today computers are hardly used in stand-alone mode. They are often connected to networks and communicate with other computers on the network. In this t...
View Full Document

This document was uploaded on 04/07/2014.

Ask a homework question - tutors are online