Hardware Information Created by Nasih

Hardware The physical components of a computer system, including any peripheral equipment such as printers, modems, and mouse devices.

Categories of Computer Hardware Central Processing Unit (CPU) Storage Primary: Cache, RAM Secondary: Hard disk, removable (e.g., CD) I/O Input Devices Output Devices

Central Processing Unit (CPU) The Central Processing Unit (CPU), also called the processor, is the “brain” of the computer. Example: CPU type Intel Pentium 4/AMD Athlon (Windows PCs) Intel Itanium2 (servers) Qualcomm MSM (cell phones) The CPU consists of three main parts: Control Unit Arithmetic/Logic Unit Registers

CPU: Control Unit Control Unit : Control all process inside CPU memory operations: for example, load data from main memory (RAM) into the registers; store data from the registers into main memory; arithmetic/logical operations: control arithmetic and logical decision

CPU: Arithmetic/Logic Unit The Arithmetic/Logic Unit (ALU) performs arithmetic and logical operations. Arithmetic operations: e.g., add, subtract, multiply, divide, square root, cosine, etc. Logical operations: e.g., compare two numbers to see which is greater, check whether a true/false statement is true, etc.

CPU: Registers Registers A high-speed memory within a microprocessor or other electronic device, used to hold data for a particular purpose. registers hold the operands being used by the current arithmetic or logical operation, or the result of the arithmetic or logical operation that was just performed. For example, if the CPU is adding two numbers, then the addend is in some register, the augends is in another register, and after the addition is performed, the sum shows up in yet another register

Storage Primary Secondary Cache Main memory (RAM) Hard disk Removable (e.g., CD, floppy)

Primary Storage Primary Storage the main general-purpose storage region to which the microprocessor has direct access, or data and instructions reside in it when they’re being used by a program that is currently running. Primary Storage is volatile: The data disappear when the power is turned off.

Secondary Storage The data and instructions reside that are going to be used in the future This type is not Nonvolatile: data don’t disappear when power is turned off. Therefore much:- Cheaper Slower Most of them are portable: they can be easily removed from your computer and taken to someone else’s.

Memory (RAM) RAM ( Random Access Memory) “Waiting room” for computer’s CPU. Holds instructions for processing data, processed data, and raw data. Ram is measured by: Capacity (in Megabytes or Gigabytes) Speed (in Nanoseconds)

Storage Technology Electronic devices that store, retrieve, and save instructions and data. Today’s microcomputers or PCs include several types of storage devices. Capacity and speed are important considerations when selecting a new storage device for a PC.

Storage Technology Magnetic storage devices store data by magnetizing particles on a disk or tape. They have a limited life-span of 1 to 5 years, depending on the device. Magnetic storage is non-volatile Ex: Hard drive Optical storage devices store data as light and dark spots on the disk surface. stores information in deformities on the surface of a circular disc and reads this information by illuminating the surface with a laser diode and observing the reflection Optical disc storage is non-volatile Ex: CD CDROM. DVD

Storage Technology Semiconductor :- uses semiconductor-based integrated circuits to store information. A semiconductor memory chip may contain millions of tiny transistors or capacitors. Both volatile and non-volatile forms of semiconductor memory exist RAM For volatile non-volatile semiconductor memory known as flash memory

Storage Devices Hard Disk Drives Capacity is measured in gigabytes (GB or billions of bytes). Typically permanently installed. Used to store operating system, application software, utilities and data. Magnetic storage device.

Storage Devices CD-ROM Drives Typically installed on all new computer systems. (Were add-on device until the mid 1990’s). Capacity is 600 to 750 megabytes (MB or millions of bytes). Most mass-produced commercial software is packaged on a CD.

Input devices A peripheral device whose purpose is to allow the user to provide input to a computer system. Example:- Keyboard, mouse, scanner, joystick, TrackPoint, .. etc

Most common input device; used to type in commands and data. Primary input device: Keyboard – Most common input device; used to type in commands and data. 2. Mouse or trackball enhances user’s ability to input commands, manipulate text, images. 3. Scanners are peripheral input devices which allow users to import: Text Graphics Images

Digital Cameras are peripheral input devices that allow users to create pictures and/or movies in a digital format. Some require specialized software to import images into the computer. Some record digital images directly to a disk that can be read by the computer.

Output devices A piece of hardware that can be used for receiving data from computer. Example:- Printer, plotter, speaker … etc.

Output Devices Monitors are the most commonly used output device. Most monitors use a bitmap display. Divides the screen into a matrix of tiny square “dots” called pixels. The more “dots” a screen can display, the higher the resolution of the monitor.

Output Devices Monitors are connected to a computer system via a port integrated on the video adapter or graphics card. Graphics cards convert digital data output from software to analog data for display on monitors.

Output Devices Printers Dot matrix Bubble or ink jet Laser Seldom used in a classroom. Still frequently used in business. Bubble or ink jet Laser

Output Devices Projection systems or classroom TVs can display information from a computer system on a larger screen for whole-class instruction.

Computer Measurement units 1- Bit (Binary digIT) Has 2 possible values that we can think of in several ways: Low or High: Voltage into transistor Off or On: Conceptual description of transistor state False or True: Boolean value for symbolic logic 0 or 1: Integer value Bits aren’t individually addressable: the CPU can’t load from or store into an individual bit of memory.

Byte: a sequence of 8 contiguous bits (typically) On most platforms (kinds of computers), it’s the smallest addressable piece of memory: typically, the CPU can load from or store into an individual byte. Possible integer values: 0..255 or -128..127 Can also represent a character Word: a sequence of 4 or 8 contiguous bytes (typically); i.e., 32 or 64 contiguous bits

Binary The binary number system has 2 as its base, so values are expressed as combinations of two digits, 0 and 1. These two digits can represent the logical values true and false as well as numerals, and they can be represented in an electronic device by the two states on and off, recognized as two voltage levels. Therefore, the binary number system is at the heart of digital computing

Binary via Decimal