CSE1100 Lecture - Computer Hardware 1 PDF

CSE1100: Introduction to Computing 1 Lecture : Computer Hardware  What is a computer? First designed and built in the 1940s - Alan Turing, John von Neumann A machine that can store both instructions (programs) and data in its memory and execute those instructions. Composed of...

CSE1100: Introduction to Computing 1 Lecture : Computer Hardware  What is a computer? First designed and built in the 1940s - Alan Turing, John von Neumann A machine that can store both instructions (programs) and data in its memory and execute those instructions. Composed of both internal and external components  Operations of a Computer Op. No. Operation Description The process of entering data and instructions into the 1 Take Input computer system. Saving data and instructions so that they are 2 Store Data available for processing as and when required. Performing arithmetic, logical operations on data in 3 Processing Data order to convert them into useful information. Output The process of producing useful information or results Information for the user, such as a printed report or visual display. 4 Control the Direct the manner and sequence in which all of the above 5 workflow operations are performed. General Computer Architecture  The System Unit What is the system unit? system unit Ø Case that contains electronic components of the computer used to process data § Sometimes called the chassis system unit system unit system unit  Components of the System Unit What are common components inside the systemunit? Ø Processor power supply drive bays Ø Memory Ø Adapter cards processor § Sound card § Modem card memory § Video card ports § Network card Ø Ports Ø Drive bays Ø Power supply sound card modem card video card network card  The System Unit What is the motherboard? Ø Main circuit adapter cards processor chip board in system unit Ø Houses adapter cards, processor memory chips chips, and memory chips Ø Also called system board memory slots Expansion slots for adapter cards motherboard  The System Unit dual inline packages (DIP) What is a chip? holds memory chips Ø Small piece of semi-conducting material on which integrated circuits are etched § Integrated circuits contain many microscopic pathways capable of carrying electrical current Ø Chips are packaged so they can be attached to a circuit board pin grid array (PGA) package holds processor chips  Central Processing Unit What is the central processing unit (CPU)? Ø Interprets and carries Processor out basic instructions Control Control Arithmetic that operate a computer Unit Unit Logic Unit (ALU) § Control unit directs and Instructions coordinates operations in Data computer Information § Arithmetic logic unit (ALU) performs Input Output Devices Data Memory Information Devices arithmetic, comparison, and logical operations Instructions Ø Alsocalled the processor, Data Information microprocessor Storage Devices  Central Processing Unit The control unit repeats four main operations: – Fetch – calls the next instruction form main memory – Decode – translate the instruction into commands the computer can process – Execute – carry out the instruction – Store - write the instructions in memory.  Central Processing Unit A machine cycle Ø Four operations of the CPU comprise a machine cycle  Central Processing Unit What is pipelining? Ø CPU begins fetching the second instruction (set) before completing machine cycle for first instruction Ø Results in faster processing  Central Processing Unit What is a register? Ø Temporary high-speed storage area that holds data and instructions Ø Stores location from where instruction was fetched Ø Stores instruction while it is being decoded Ø Stores data while ALU computes it Ø Stores results of calculation  The Electronic Clock What is the system clock? Ø Regulates timing and speed of all computer operations Ø Generates regular electronic pulses, or ticks, that set operating pace of components of system unit Pace of system clock is clock speed Each tick (0-1-0) Processor speed can Most clock speeds are is a also be measured in in the gigahertz (GHz) clock pulse millions of instructions range (1 GHz = one representing one cycle per second (MIPS) billion ticks of system clock per second)  Buses What is a bus? Ø A set of wires that facilitate communication. Ø Connects two or more components. § System buses connects processor and memory § Bus width determines number of bits transmitted at one time § Word size is the number of bits the processor can interpret simultaneously. It is usually larger than a byte, e.g., 8, 16, 32 or 64 bit word sizes  Buses CPU connects to main memory by 3 separate buses – Address bus – used to send addresses to memory or I/O controller – Data bus – used to transmit data (binary) – Control bus – carries signals to tell whether to read or write from memory or I/O controller  Memory What is memory? Ø Semi-conductors used for data storage Ø Each byte stored in unique location called an address Ø Memory stores three basic categories of items: 1) Operating system and other system software 2) Application programs 3) Data and the resulting information ,  Memory What is random access memory (RAM)? Memory chips that can be read from and written to by processor Most RAM is Also called volatile, it is lost main memory when computer’s or primary power is storage turned off The more RAM a computer has, the faster it responds  Memory What are three basic types of RAMchips? Used for Most Static special common RAM applications type such as (SRAM) cache Faster variations Dynamic Faster and of DRAM are RAM more reliable SDRAM and (DRAM) than DRAM RDRAM chips Dynamic RAM (DRAM) – transistors that store an electric charge; leaks quickly Static RAM (SRAM) –more expensive than DRAM, Magnetoresistive RAM (MRAM): uses less power; more storage capability; faster access time; stable; more expensive. Aka Flash RAM  Memory How much RAM do you need? Ø Depends on type of applications you intend to run on your computer RAM 128 to 256 MB 256 to 1 GB 1 GB and up Use Home and business Users requiring more advanced Power users creating users managing multimedia capabilities professional Web sites personal finance Running number-intensive Running sophisticated Using standard accounting, financial, or CAD, 3D design, or application software spreadsheet programs other graphics-intensive such as word processing Using voice recognition software Using educational Working with videos, music, and or entertainment digital imaging CD-ROMs Creating Web sites Communicating with Participating in video conferences others on the Web Playing Internet games  Memory What is read-only memory (ROM)? Memory chips that store Nonvolatile memory, it is not permanent data lost when computer’s and instructions power is turned off Aka Firmware— Manufactured with permanently written data, instructions, or information PROM (programmable read-only memory)—Blank ROM chip onto which a programmer can write permanently EEPROM (electrically erasable programmable read-only memory)— Type of PROM containing microcode that a programmer can erase  Memory What is flash memory? Ø Nonvolatile memory that can be erased electronically and reprogrammed Ø Used with PDAs, digital cameras, digital cellular phones, music players, digital voice recorders, and pagers Step 3. Step 1. Plug the headphones into the MP3 Purchase and download MP3 music tracks To player, push a button on the MP3 from a Web site. With one end of a special Flash memory headphones player, and listen to the music cable connected to the system unit, connect chip through the headphones. the other end into the MP3 player. From computer Flash memory card Step 2. Instruct the computer to copy the MP3 music track MP3 to the flash memory chip in the MP3 player. Player p. 4.21 Fig. Next 4-24  Memory What is CMOS? Complementary Used in some metal-oxide RAM chips, flash semiconductor memory chips, and memory other types of memory chips Uses battery Stores date, power to retain time, and information when computer’s other power is startup turned off information  Memory What is access time? Ø Amount of time it takes processor to read data from memory Ø Measured in nanoseconds (ns), one billionth of a second Ø It takes 1/10 of a second to blink your eye; a computer can perform up to 10 million operations in same amount of time Term Speed Millisecond One-thousandth of a second Microsecond One-millionth of a second Nanosecond One-billionth of a second Picosecond One-trillionth of a second