External Devices

External Devices

1. Provide a means of exchanging data between the external environment and the computer

2. Attach to the computer by a link to an I/O module

   • The link is used to exchange control , status , and data

3. Peripheral device

   • An external device connected to an I/o module

4. Three Categories

   • Human readable
     • suitable for communicating with the computer user
     • Video display terminals , printers
   • Machine readable
     • Suitable for communicating with equipment
     • Magnetic disk and tape systems
   • Communication
     • Suitable for communicating with remote devices