Chapter 6 Input / Output

Chapter 6 Input / Output

1. External Devices

   • Three categories: Human readable, Machine readable, Communication

2. Keyboard/Monitor

   • International Reference Alphabet (IRA)
   • Keyboard Codes

3. Three techniques are possible for I/O operations

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

4. Universal Serial Bus (USB)

5. Device Identification

   • Multiple interrupt lines Software poll Daisy chain (hardware poll, vectored) Bus arbitration (vectored)

6. I/O Mapping Summary

   • Memory mapped I/O Isolated I/O

7. I/O Commands

   • Control Test Read Write