Computer Organization

Front 1

five classical components of computer

Back 1

input

output

memory

datapath

control

Front 2

basic operations of computer

Back 2

arithmetic

data transfer

logical

conditional branch

jump

Front 3

levels of program language

Back 3

high level language

assembly language

hardware representation

Front 4

layers below your program

Back 4

application software

system software (compiler, operating system)

hardware (processor,memory, IO)

Front 5

number bases

Back 5

binary (2)

octal (8)

decimal (10)

hexadecimal (16)

Front 6

solution negative numbers

Back 6

two's complement for signed numbers:

leading zero's means positive (MSB)

leading one's means negative (MSB)

in MIPS 32 bit word, the middle word with one leading one and rest of zero's, does not have positive complement

Front 7

MSB,LSB

Back 7

Most Significant Bit, Least Significant Bit

Front 8

negating two's complement number

Back 8

invert

add 1

Front 9

two's complement: word length change

Back 9

for example from 8 bits to 16 bit

Copy MSB into empy bits

Front 10

overflow

Back 10

result of operation is too large for finite computer word

Front 11

detecting overflow

Back 11

no overflow:

when adding positive and negative numbers

signs are the same for subtraction

occurs when the value affects the sign of the result

Front 12

Instruction Set Architecture (ISA)

Back 12

abstract interface between hardware and lowest-level software, that encompasses all the informattion necessary to write a machine language program that will run correctly

Front 13

stored-program concept

Back 13

the idea that instructions and data of many types can be stored in memory as numbers

Front 14

memory conflicting requirements

Back 14

fast, large and cheap

solution: hierarchy of memory

from top to bottom: fast to slow

Front 15

memory: registers and main memory

Back 15

MIPS:

provides 32 register with word size (32 bit)

use byte address to access main memory

Front 16

memory access instructions

Back 16

lw

load word from memory into register

sw

store word from register into memory

offset

use offset to access array elements in base address

[pay attention to word size (bytes), this will scale the offset]

Front 17

logical operations

Back 17

SHIFT

sll (shift left logical)

srl (shift right logical)

AND

and (mask bits in word, result displays 1 only if both operands contain 1)

OR

or (include bits in word, places 1 in result if either operand is a bit)

NOT

nor (invert bits in word)

Front 18

conditional branch & unconditional jump

Back 18

branch to labeled instruction if condition is true

beq (both are equal)

bne (both are unequal)

jump to instruction

j

Front 19

program counter (PC)

Back 19

implicit in the stored-program concept is the need to have a register to hold the address of the current instruction being executed

points to next instruction to be executed

Front 20

Arithmetic-Logic Unit (ALU) purposes

Back 20

address calculations of memory-reference instructions

operation execution of arithmetic-logical instructions

comparison for branches

Front 21

spilling registers

Back 21

putting less commonly used variables into memory as solution to

programs uses more variables than computer has registers

Front 22

steps of executing a program

Back 22

Fetch instructions

Decode instructions

Fetch data (from memory to processor registers)

Execute instructions

Store results (memory or registers)

Change PC (points to following instruction)

Repeat (go to step one)