TELETEXT O F VIDEO TEXT SYSTEM
Videotext is a two-way information service as video display unit or crt terminal.This information service generally provides data in 4 major areas,
1. Finance stock exchanges
2. Money markets and reservation
3.Messaging- topical news and reviews a subscriber to database can select desired information via keypad accessory.
4. Prestel - first video text service.
View data systems use all kinds of host computers, from minicomputers to mainframes depends upon power require for service.
It performs most of hardware functions of a viewdata terminal- autodialer circuit, band demodulator and asynchronous receiver, baud modulator and asynchronous transmitter. It includes a tape interface for recording and character codes. View data terminals CRT displays are used to display the information for viewing and editing. It can be an intelligent terminal or microcomputers. Intelligent terminals- equipped with microprocessor and data storage memory capacity to process the data. Microcomputers – with software for data storage and local processing capability. TV monitor is enhanced with video bandwidth to improve resolution as CRT display monitor or VDU.