Chapter 6 Input/Output

Chapter 6 Input/Output

1. Buffer

   • Temporarily hold data being transferred between I/O module and external environment

2. Transducer

   • vvv
   • Converts data fro electrical to other forms of energy

3. 3 Catergories of external devices

   • Human readable (keyboard),Machine readable (magnetic disk),Communication (router)

4. Keyboard/Monitor

   • Printable - alphabetic,numeric,special character
   • Control - control the printing or displaying characters

5. Programmed I/O

   • Programmed I/O, Interrupt driven I/O, Direct memory access (DMA)

6. I/O Commands

   • Control, Test, Read, Write

7. I/O Mapping Summary

   • Memory mapped I/O
   • Isolated I/O

8. Device Identification

   • Multiple interrupt lines
   • Software poll
   • Daisy chain
   • Bus arhitration

9. Drawbacks

   • transfer rate is limited by the speed

10. Evolution of I/O Function

    • CPU directly controls a peripheral device

11. Universal Serial Bus (USB)

    • For slower speed devices

12. FireWire Serial Bus

    • IEEE standard 1394, for High Performance Serial Bus