Chapter 6 Data Terminals and Personal Computers Agenda

Chapter 6 Data Terminals and Personal Computers

Agenda • • • Terminals Cluster control units Workstation ergonomics Terminal selection criteria Total cost of ownership of personal computer

Terminal Classification • Definition – Input/output devices – Data terminal equipment (DTE) – Data circuit-terminating equipment (DCE) • Classification – – – Teletypewriters Video display terminals (VDTs) Personal computers Industry-oriented transaction terminals Intelligent terminals Specialized terminals

Teletypewriter Terminals • Types – Unbuffered – Buffered • Characteristics – Slow speed – Mechanical dot matrix printing – Hard copy

Video Display Terminals (VDT) - I • Types – Cathode ray tube terminal (CRT) – Flat panel displays • Characteristics – Electronic – Reliable – Buffered – High speed – Unintelligent - intelligent

Video Display Terminals (VDT) - II • Screen – – – All-point-addressable (APA) Pixels or pels Line-by-line mode Page or formatted mode Intensifying, blink, or reverse video • Keyboard • Alternative input mechanisms – – Touch-sensitive Joystick Trackball Mouse

Video Display Terminals (VDT) - III • Selection criteria – Nonglare surface – Titled or swiveled mechanism – Color or monochrome – Image flickfree – Size – Resolution – Programmable – Graphics capability

Personal Computers • Types – Microcomputer (portable, laptop, or notebook) – Workstation – Internet computers • Characteristics – Upload and download (FTP) – Terminal emulation program & hardware (DEC VT-, IBM 3270) – Graphical user interface (GUI) – Multitasking • Virus

Others • Industry-oriented transaction terminals – ATM & point of sale • Remote job entry • Facsimile machines – Group I, III, III enhanced, super III, IV – Security problems (audio cassette recorder) • Specialized terminals – Telephone – Optical recognition (bar code reader, optical character recognition (OCR)) – Other terminals for counting, weighing, measuring, and reporting results to the computer

Terminals Intelligence • Intelligent terminals: program & storage capability • Smart terminals: storage capability • Dumb terminals: no or limited storage capability

Cluster Control Units • Characteristics – Program capability – Buffers • Functions – – – Control terminals Code conversion Error checking Share printer Access multiple computers Multiple sessions using hot key

Workstation Ergonomics • • Nonglare screen Tilted back 10 to 20 degrees Top of screen is eye level 18 inches from eyes Adjustable chair Movable keyboard Proper lighting

Terminal Selection Criteria • • Special or general Hardcopy or video display Types of operators Compatibility with the existing equipment Degree of intelligent Cost Vendor support and service

Total Cost of Ownership • Cost – – – $6, 400 to over $13, 000 lifetime Hardware & software cost – 20% User operational cost (learning & training) – 46% Technical support cost – 21% Administrative cost – 13% • Control – Centralized management – Standardizing hardware and software

Points to Remember • • • Terminals Cluster control units Workstation ergonomics Terminal selection criteria Total cost of ownership of personal computer

Discussion • Design terminal requirement for a big manufacturing company • Design terminal requirement for a big insurance company