Lecture4

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

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Input Devices

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Output Devices

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Standard Interfaces

Output Devices

Standard Interfaces

Input Devices

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Input Devices

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Output Devices

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Output Devices

Standard Interfaces

Input Devices

Output Devices

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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

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Input Devices

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Output Devices

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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

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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

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Input Devices

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Output Devices

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Standard Interfaces

Output Devices

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Input Devices

Output Devices

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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