Input Devices
Output Devices
Standard Interfaces
CS 21 - Computer Organization and Assembly Language Programming Lecture 4 I/O Devices, Peripheral Devices and Buses
University of the Philippines - Diliman College of Engineering Department of Computer Science
Input Devices
Outline
1
Input Devices
2
Output Devices
3
Standard Interfaces
Output Devices
Standard Interfaces
Input Devices
Outline
1
Input Devices
2
Output Devices
3
Standard Interfaces
Output Devices
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
I/O and External Devices
a computer system is useless without some form of input or output I/O operations are accomplished through External Devices
Input Devices
Output Devices
Common Input Device
Microphone
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Microphone Technology behind the microphone getting sound to a computer takes two steps 1
2
an acoustic-to-electric transducer or sensor that converts sound into an electrical signal an ADC or Analog to Digital Converter converts continuous electrical signal to binary codewords
Input Devices
Output Devices
Common Input Device
Keyboard
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Keyboard
Technology behind the keyboard array of switches key pressed determines binary pattern sent to the computer
Input Devices
Output Devices
Common Input Device
Mouse
Standard Interfaces
Input Devices
Output Devices
Mouse Technology behind the mouse buttons are simple switches cursor movement detected via light sensors.
Standard Interfaces
Input Devices
Output Devices
Common Input Device
Webcam
Standard Interfaces
Input Devices
Output Devices
Common Input Device
Digital camera
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Webcam and Digital Camera Technology behind image sensing devices like the microphone, getting an image to a computer takes two steps 1
2
CCD(charge coupled device) sensors convert light to a continuous electrical signal additional circuit converts the electrical signal to pixel-by-pixel digital(discrete) information
Input Devices
Output Devices
Taking it a even further
Microsoft XBOX 360 Kinect
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Microsoft XBOX 360 Kinect Technology behind Microsoft XBOX 360 Kinect webcam takes video of player player movement is analyzed and converted to data, which translates to game control
Input Devices
Output Devices
Common Input Device
Touch Screen
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Touch Screen Technology behind Touch Screen Devices created by placing extra layers above a display device several variations of the technology exist: upon contact, either conduction or change in electrical charge is measured and then the coordinates are the sent to the computer
Input Devices
Output Devices
Not-so-common(yet) Input Device
Wii
Standard Interfaces
Input Devices
Output Devices
Not-so-common(yet) Input Device
iPod
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Wii and iPod Technology behind Wii and iPod accelerometers detect motion - one accelerometer per axis of motion the accelerometer contains a mass whose displacement is then sensed displacement magnitude and speed is converted to digital signal
Input Devices
Outline
1
Input Devices
2
Output Devices
3
Standard Interfaces
Output Devices
Standard Interfaces
Input Devices
Output Devices
Common Output Device
Cathode Ray Tube Monitor
Standard Interfaces
Input Devices
Output Devices
Cathode Ray Tube Monitor Technology behind Cathode Ray Tube Monitor electron beam forms images on a fluorescent screen bending of electron beam controlled by computer line by line refreshed
Standard Interfaces
Input Devices
Output Devices
Common Output Device
Liquid Crystal Display Monitor
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Liquid Crystal Display Monitor Technology behind Liquid Crystal Display Monitor liquid crystals modulate light - by how much is electrically controlled the crytals do NOT emit light themselves more energy efficient than CRTs
Input Devices
Output Devices
Common Output Device
Speakers
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Speakers Technology behind speakers steps in generation of sound are reverse of that found in the microphone 1
2
digital signals in binary from the computer are converted by a DAC(Digital to Analog Converter) to a continuous electrical signal electrical signal is converted to sound by an electric-to-acoustic transducer
Input Devices
Output Devices
Common Output Device
Printer
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Printer Technology behind the printer two points of control: ejection of ink(in case of inkjet printers), and servo motor which moves the printer head servo motors are motors whose position and motion could be electronically controlled
Input Devices
Output Devices
Common Output Device
Cellular phone
Standard Interfaces
Input Devices
Output Devices
Common Output Device
Playstation’s Dualshock controller
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Cellphones and Playstation’s Dualshock controller Technology behind Cellphones Playstation’s Dualshock controller players feel vibration through the controller and cellphone’s vibrator
Input Devices
Output Devices
Not-so-common Output Device
Virtual Hugging Vest
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Virtual Hugging Vest Technology behind the Virtual Hugging Vest hugging vest is controlled by your chatmate when he or she wants to �hug� you, he presses software button and the vest tightens
Input Devices
Outline
1
Input Devices
2
Output Devices
3
Standard Interfaces
Output Devices
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Peripheral Component Interconnect
standard for connecting controllers slots for network card, modem, sound card, slow videocards originally design for 133MB/s transfer rate, now can go up to 1GB/s
Input Devices
Output Devices
Peripheral Component Interconnect - Express
improvement over the original PCI competes with AGP when it comes to video cards varies in length or number of connectors
Standard Interfaces
Input Devices
Output Devices
Standard Interfaces
Universal Serial Bus
attempts to standardize how devices connect to the personal computer up to 127 devices can connect to a single port continuous improvement in speed, but with backwards compatibility small devices could be powered via the USB port itself
Input Devices
USB Swiss Army Knife
Output Devices
Standard Interfaces
Input Devices
USB Eye Warmer
Output Devices
Standard Interfaces
Input Devices
USB Mini Fridge
Output Devices
Standard Interfaces