Computer Peripherals Sumary for Computers Vocational trainning
- 2. • Peripherals (concept, parts, interconnection, communication) • Input Peripherals • Output Peripherals • Input/Output Devices 2
- 3. Peripheral Concept 3 • A peripheral connects the PC to the outside world • Serves as an intermediary with the PC user • There are 3 types of peripherals: • Input • Output • Input/Output
- 4. Parts of a Peripheral 4 • Every peripheral is made up of • A mechanical part • An electronic part that controls the mechanical part (controller)
- 5. Peripheral-CPU Interconnection 5 • Peripheral-CPU and Peripheral-RAM communication has evolved over time: • Stage 1: peripherals were connected directly to the system bus (RAM depends on the CPU). • Stage 2: RAM connects to the bus independently of the CPU. • Stage 3: An I/O controller is incorporated (peripherals do not connect to the system bus). • Stage 4: a bus is added that adapts speed differences. • Stage 5: incorporation of DMA (direct memory access).
- 6. Peripheral-CPU Interconnection 6 • Current interconnection scheme:
- 7. Peripheral-CPU Communication 7 • Peripherals need RAM to function (Von Neumman architecture). • The CPU is usually used as an intermediary for this communication. • Different mechanisms. • Programmed Input/Output: The CPU decides when the information transfer starts. • Interruptions: the peripheral starts the transfer, interrupting the processor. • Direct Memory Access (DMA): the peripheral has direct access to memory. • Notifies memory when the transfer is complete.
- 8. • Peripherals (concept, parts, interconnection, communication) • Input Peripherals/DEvices • Output Peripherals/Devices • Input/Output Devices 2
- 9. Keyboard 9 • Consists of a contact matrix and a microprocessor • Different keyboard layouts (QWERTY is the most common) • Different types of keyboards (ergonomic, multimedia, etc.) • With wired (usually USB) or wireless connection • Keyboard Logitech K120 (Source PCComponentes) • Inside a Keyboard (contactor and processor matrix) (Source Quora)
- 10. Mouse 10 • Implemented by Xerox in the 70s. • Various implementations exist. • Mechanical mouse (plastic ball). • Optical mouse (optical sensor). • Laser mouse (laser sensor). • TrackBall (like the mechanical one but ball above the mouse). • With wired or wireless connection. • Mouse Logitech M185 • Source PCComponentes
- 11. Scanner 11 • Allows images to be entered into the PC. • Can also recognize text (with OCR software). • There are different types: • CCD scanner (CCD sensor, photosensitive diodes) • CIS Scanner (glass lenses with LED light, the most used) • Depending on the size: portable, flat, barcode,… • With wired (USB or Ethernet) or wireless connection. • Automatic scanner • Brother ADS1200 • Source PCComponentes
- 12. • Peripherals (concept, parts, interconnection, communication) • Input Peripherals/Devices • Output Peripherals/Devices • Input/Output Devices 2
- 13. Monitor 13 • Connects to the graphics card and displays images. • Considerations: point size, resolution, aspect ratio. • Different types (link): • CRT (Cathode Ray Tube). • LCD (Liquid Crystal Display). • TFT (Thin Film Transistor, variante de LCD). • OLED y AMOLED (Organic LED) • Plasma. • BenQ GW2780T 27’’ • LED IPS Eye-Care (Source PCComponentes) • CRT Monitor (Source posiberica)
- 14. Printer 14 • Prints data or files (from software or operative system) • Considerations: • Print speed, resolution, interface • Printing cost per page • Different types: • Inkjet • Laser • Thermal • Matrix • Multifunction (input/output) • Brother HL-L2445DW • Monocrome laser Source PCComponentes
- 15. • Peripherals (concept, parts, interconnection, communication) • Input Peripherals/Devices • Output Peripherals/Devices • Input/Output Devices 2
- 16. Touchscreen 16 • These are monitors with added touch functionality. • There are different types: • Resistive screens: • They have several layers • When pressed, a change occurs and pulsation is detected. • Capacitive screens • Its surface is charged • When the flow of current is interrupted, a pulsation is detected • Posiflex TM-3315 • TouchScreen 15’’ Source PCComponentes