Input/Output of a Computer by lpPDmn


									Input/Output of a Computer

        Presented by:
       Jose Reyes Jose

 What is input and output?
 Different types of I/O interfaces
 Examples of input devices
 Examples of output devices
                 Input and Output

The collection of interfaces that different functional units
(sub-systems) of a system use to communicate with each
other, or to the signals(data) sent through those interfaces.
Inputs are the signals received by the unit, and outputs are the
signals sent from it. I/O devices are used by a person (or
another system) to communicate with a computer.

In General:
      Input and output allows the
computer to obtain information from the
outside world, and send the results of its
work back to it.
          Different types of I/O

 Programmed I/O

 Interrupt Drive I/O

 Direct Memory Access
                  Programmed I/O

The programmed I/O(PIO) interface was the original method
used to transfer data between the CPU (through the IDE
controller) and device. The PIO interface is grouped into
different modes that correspond to different transfer rates. The
electrical signaling among the different modes is similar - only
the cycle time between transactions is reduced in order to
achieve a higher transfer rate. All devices support the slowest
mode - Mode 0. By accessing the information registers, the
CPU is able to determine the maximum transfer rate for the
device and configure the IDE controller for optimal

 an interrupt is a signal from a device which
  typically results in a context switch.
 Interrupts were originated to avoid wasting
  the computer's valuable time waiting for
  electronic events.
 Instead, the computer was able to do other
  useful work while the event was pending.
    Direct Memory Access(DMA)

 A smart I/O that can transfer data into
  memory directly
 Far more efficient than Programmed and
  Interrupt I/O
 Allows CPU to execute other instructions
  while I/O is being performed
      Examples of input devices

 Keyboard/Mouse
 Scanner
 CD-Rom
 Game Controller
 Digital Camera
     Examples of output devices

 Monitor
 Printer
 Speakers
        Input/Output Devices

 Hard Drive
 Mp3 Player
 Flash Memory
 CD/DVD Burners

 It had never been easier to connect a device
  to your computer.
 Many of today’s devices plug into the
  computer using the USB port.
 USB port is very versatile

To top