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35 Cards in this Set
- Front
- Back
what two components are in the CPU and what do they do?
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Control Unit: Responsible for flow of info to and from the CPU
ALU: accessed by the control unit when the instruction involves an arithmetic or logical operation -contains registers |
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what are registers?
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used for data storage while data is being transferred back and forth between the CPU and the main memory
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what is the Instruction Register?
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stors address of the next instruction in the main memory, to be executed -> also called program counter
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what is the instruction register?
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stores the binary code for each low level instruction as it is being executed
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what is the data register?
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used to store processed of unprocessed data
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what is the address register?
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used to store addresses of data in the main memory
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what are some other CPU components other than the ALU and the control unit?
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instruction pointer, instruction register, data register, address register, accumulator, control lines, and instruction decoder
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what is the accumulator?
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a register that the ALU uses to store the result of an arithmetic logical operation
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what are control lines?
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enable the loading and unloading of registers
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what is the instruction decoder
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translates the binary code in the instruction register to actual CPU operations
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What two operations does the CPU continuously perform?
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1) Fetch Instruction (I-Time)
2) Execute Instruction (E-Time) -look at pic in package |
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what are the CPU operations in I-Time?
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1. instruction stored at memory address is retrieved
2. binary opeation code is latched into instruction register 3. address currently held in the instruction pointer is incremented to prepare for the next fetch from memory 4. operation code stored in the instruction register is deciphered |
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What are the CPU operations in E-Time?
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1. execute the instruction. which can involve 1/3 things
1)if requires arithmetic or logical operations ->signal ALU to perform and record result in accumulator 2) the operation may involve the relocation of data from memory loation to register or vice versa 3) the operation may simply require that a new address be put into the instruction pointer |
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what is main memory?
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-electronic circuitry directly linked to processor and used in compuer to store data and programs
-located on motherboard |
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what are four main memory types?
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RAM (random access memory)
Virtual Memory ROM (Read only Memory) CMOS (complemntary metal-oxide semicoductor |
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What are the properties of RAM?
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1)randomly accessible
2)modifiable 3)volatile 4)stores data and programs heading towards the cpu and also processed data going from the cpu to various i/o |
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what IS RAM?
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collection of electronic cicuits etched onto silcon chips
-chips added on top of carrier packages arranged on boards (SIMMs and DIMMs) |
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What is DRAM?
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Dynamic RAM -requires recharging,
-during recharge process, memory is not available |
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what is SRAM?
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Static RAM
- no recharging, f -aster and more expensive than DRAM -used for cache |
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SDRAM
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Synchronous Dynamic RAM
-all operations and signals are synchronized with the system clock |
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What is DDR SDRAM?
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double data rate SDRAM
-activates output on both rising and falling edge of the system clock (doubling output) |
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What is RDRAM?
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Rambus Dynamic RAM
-new technology developed by Rhambus corp. RAM speed 800 MHz |
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What is DRDRAM
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Direct Rambus Dynamic RAM
uses pipelining -up to 8 operations mayb e underway at at time |
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what Virtual RAM? What are some properties?
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refers to the part of the hard disk which is used as an extension of RAM to enable use of large programs
-move least used applications here when RAM insufficient -modifiable -volatile |
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what is properties of ROM?
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-permanent, even when power is off
-used to store start up instructions (BIOS) |
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Name some various types of ROM chips
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PROM(programable ROM)- only used once
EPROM-(Erascable Programable) - can be erased by exposing to ultraviolet light EEPROM (electronically Erasable Programable ROM) - can be erased by exposing to electrical charge also called flash memory |
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What is CMOS RAM memory?
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-used macintosh
-semi-permanent -> compromise between ROM and RAM ->low energy -used to store information needed for start up |
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what are some other mother board components?
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buses - circuits etched into board, acts as wires needed to transport data
ports- provide connections for I/o devices and peripherals |
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name 4 different types of ports?
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1)serial port
2)parallel port 3)USB port 4)firewire (IEEE 1394) |
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What is a serial port?
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1) serial port
- 1 bit transmittion, inexpensive, used to connect scanners and modems -9pins |
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what is a parallel port?
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-transmits 1 byte at a time
-more expensive wire -connects devices like printers and tape drives |
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what is a USB port?
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-universal serial bus
-transfers are in parallel -faster than parallel -can auto detect |
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what is firewire IEEE 1394?
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-extremely high speed 400 MB a second
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What are some other mother board components?
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expansion slots, expansion cards, and bays
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what are some factors affecting CPU speed?
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1) system clock's frequency: faster frequency means faster instruction cycle
2) word size: larger word size smaller instruction cycles 3) cache size: more info can be held in cache -> larger word size -> fewer instruction cycles 4)pipelining: allows cpu to begin executing an instuction before the previous one was completed 5) parallel processing: process more than one instruction at a time |