Chapter 5 - Hardware: input & output. The topics discussed in this chapter are: Keyboards, pointing devices, source data-entry devices, the future of input, softcopy output: display screens, hardcopy output: printers, mixed output: sound, voice, & video, the future of output, quality of life: health & ergonomics. | Chapter Hardware: Input & Output 5 1 Chapter Topics 2 UNIT 5A: Input Hardware Keyboards Pointing Devices Source Data-Entry Devices The Future of Input UNIT 5B: Output Hardware Softcopy Output: Display Screens Hardcopy Output: Printers Mixed Output: Sound, Voice, & Video The Future of Output Quality of Life: Health & Ergonomics Input Hardware Devices that translate data into a form the computer can process Translates words, numbers, sounds, and pictures into binary 0s and 1s (off or on electrical signals or light pulses) Output Hardware Devices that translate information processed by the computer into a form humans can understand Translates binary code into words, numbers, sounds, and pictures 3 UNIT 5A: Input Hardware The three major types of input hardware are keyboards, pointing devices, and source data-entry devices. 4 5 Keyboards 6 Keyboards: convert letters, numbers, and characters into electrical signals English keyboards differ from . | Chapter Hardware: Input & Output 5 1 Chapter Topics 2 UNIT 5A: Input Hardware Keyboards Pointing Devices Source Data-Entry Devices The Future of Input UNIT 5B: Output Hardware Softcopy Output: Display Screens Hardcopy Output: Printers Mixed Output: Sound, Voice, & Video The Future of Output Quality of Life: Health & Ergonomics Input Hardware Devices that translate data into a form the computer can process Translates words, numbers, sounds, and pictures into binary 0s and 1s (off or on electrical signals or light pulses) Output Hardware Devices that translate information processed by the computer into a form humans can understand Translates binary code into words, numbers, sounds, and pictures 3 UNIT 5A: Input Hardware The three major types of input hardware are keyboards, pointing devices, and source data-entry devices. 4 5 Keyboards 6 Keyboards: convert letters, numbers, and characters into electrical signals English keyboards differ from foreign language keyboards How keyboards work: You press a key This interrupts the current flowing through the circuits Processor determines where the break occurs It compares the location of the break with the (x,y) character map for the language on the keyboard’s ROM chip A character is stored in keyboard memory 7 (continued) Keyboards (continued) The character is then sent to PC as a data stream via wire or wireless connection OS interprets its own operating-system-specific commands and sends the others to the application for interpretation Most keyboards are QWERTY – named for the first six letters on the top left of the keyboard. Keyboards are either tactile (physical) or touch screen (virtual) 8 Keyboard types 104 – 108 keys desktop standard 80 – 85 keys for laptops Wired Connect to CPU via a serial or USB port Wireless use either IR (infrared) technology Radio Frequency (RF) technology 9 Terminal Types Dumb Terminals . Video Display Terminal (VDT) Has display screen and keyboard
