Computer Architecture, Weeks 1-2

Front 1

Time

Back 1

Second (s)

millisecond (ms) 10^-3 second

microsecond (mew s) 10^-6 second

nanosecond (ns) 10^-9 second

picosecond (ps) 10^-12 second

Front 2

Frequency

Back 2

Hertz (Hz) = # of cycles per second

KiloHertz (KHz) = 10^3 Hz

MegaHertz (MHz) = 10^6 Hz

GigaHertz (GHz) = 10^9 Hz

Front 3

Random Access Memory

Back 3

Byte (B) = Group of 8 bits

KiloByte (KB) = 2^10 B = 1024 B

MegaByte (MB) = 2^20 B = 1024 KB

GigaByte (GB) = 2^30 B = 1024 MB

Front 4

Disk Memory (In most cases)

Back 4

Byte (B)

Sector = 512 B

KilByte (KB) = 2^10 B = 1024 B = 2 Sectors

MegaByte (MB) = 1000 KB

GigaByte (GB) = 1000 MB

Front 5

Communication Data Rate

Back 5

bits per second (bps)

Kilobits per second (Kbps) = 10^3 bps

Megabits per second (Mbps) = 10^6 bps

Gigabits per second (Gbps) = 10^9 bps

Front 6

Self Modifying Programs

Back 6

A program that modifies the address fields of instructions.

Front 7

Programmed I/O

Back 7

(Through CPU)

I/O handled by the CPU directly

Front 8

Components of the CPU

Back 8

Control Unit (CU)

Arithmetic and Logic Unit (ALU)

Registers

Front 9

Primary Memory

Back 9

RAM

Front 10

Functional Components of First Generation Machines

Back 10

Central Processing Unit

Primary Memory

Secondary or Auxiliary Storage

Input Devices

Output Devices

Interconnection Structure (Bus)

Front 11

Von Neumann Machine Model

Back 11

Memory

Control Unit

Arithmetic Logic Unit (Accumulator within that)

Input/Output

Front 12

Computer Organization

Back 12

Deals with the functional units of a computer system, their design, performance factors, and how the functional units relate to each other.

Front 13

Computer Architecture

Back 13

Deals with the aspects of a computer system a software developer should be aware of, such as CPU registers and their functionality, the instruction set, addressing, modes, etc.

Front 14

Clock Frequency (Clock Rate)

Back 14

The number of clock cycles completed per second.

Unit of measurement: Cycles per second, or Hertz (Hz).

Front 15

Clock Cycle Time

Back 15

The time to complete one clock cycle.

Unit of Measurement: second

Front 16

Clock frequency (clock rate) and clock cycle time are _______ of each other.

Back 16

Inverse

Front 17

Bit

Back 17

Binary digit

Front 18

Cell

Back 18

The smallest addressable group of bits

Front 19

Memory Address

Back 19

Location in memory of a cell containing data.

Front 20

Maximum number of addressable cells in an n bit address

Back 20

2^n

Front 21

Cell size in modern machines

Back 21

8 bits, or a byte.

Front 22

A group of bytes

Back 22

A word

Front 23

Memory Address Register (MAR)

Back 23

Holds either the address from which data will be fetched to the CPU or the address to which data will be sent and stored.

Front 24

Memory Data Register (MDR)

Back 24

Also known as the Memory Buffer Register (MBR)

Contains either the data to be stored in the computer storage (e.g. RAM), or the data after a fetch from the computer storage.

Front 25

Why is RAM called RAM?

Back 25

The access time is independent of the address.

Front 26

Little Endian

Back 26

Place least significant byte in lower address.

e.g., Intel architecture

Front 27

Big Endian

Back 27

Place most significant byte in lower address.

e.g., Motorola architecture

Front 28

What cannot be done in hardware directly may be accomplished by __________________.

Back 28

writing appropriate software.

e.g., think of a computer that can add two numbers and can be controlled to repeat some operation over and over under some circumstance; multiplication can be accomplished by repeated addition.

Front 29

Control Unit (CU)

Back 29

Controls the actions of all components in the CPU.

Responsible for instruction fetch-decode-execute cycle.

Front 30

Arithmetic and Logic Unit (ALU)

Back 30

Performs all arithmetic (addition, subtraction, multiplication, division, etc.) and logical (comparison, AND, OR, NOT, etc.) operations.

Front 31

Registers

Back 31

Temporary, high-speed memory in the CPU used to store intermediate values or special data.

Front 32

Accumulator

Back 32

A special register in the CPU that participates in several operations, such as addition and multiplication.

Front 33

Flag or condition code register

Back 33

A register that is set by most arithmetic and logical operations and consulted for conditional branches.

Front 34

Program Counter (PC)

Back 34

Contains the memory of the NEXT instruction to be executed.

Also known as the Instruction Pointer

Front 35

Instruction Register (IR)

Back 35

Contains the instruction currently being executed.

Front 36

Fetch-Decode-Execute Cycle

Back 36

Fetch:

1. Bring next instruction (pointed to by the program counter) from memory into the instruction register.

2. Change program counter to point to next sequential instruction.

Decode:

3. Determine type of instruction just fetched.

Execute:

4. If instruction uses a data in memory, locate it.

5. If needed, bring data into a CPU register.

6. Execute instruction.

Cycle Back:

7. Go to Step 1 to begin the fetch phase of the next instruction.

Front 37

LOAD N, where N is a memory address

Back 37

Load the contents of the memory cell N into the special register A (accumulator).

Front 38

Moore's Law

Back 38

Observation made in 1965 by Gordon Moore, co-founder of Intel.

The doubling of the number of transistors about every 18 months.