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, II, 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