Machine Language

Question 1

unit of storage in current computer systems is

Answer 1

a binary valued bit

Question 2

to understand machine language the first step is to understand

Answer 2

data representations using 0’s and 1’s

Question 3

text representations

Answer 3

basic ascii
extended ascii
Unicode
Strings(concatenating representations of characters)

Question 4

basic ascii is _ bits per character

Answer 4

7

Question 5

extended ascii is _ bits per character

And can be used to represent ________

Answer 5

8

characters from languages other than english

Question 6

Unicode typically is _ bits per character

Answer 6

16

Question 7

End of a string often _________

Alternatively could include _________

Answer 7

null character (all 0 bits)
alternatively could include a count of the number of characters in the string(like java)

Question 8

Represent unsigned integers

Answer 8

BCD

As base two (binary) numbers

Question 9

BCD: _____________
supports ____________
inefficient _________ & ___________

Answer 9

use 4 bits to represent each decimal digit
languages such as COBOL that have decimal data types
inefficient use of storage & arithmetic operations

Question 10

Binary #’s are ______ for computers but _________

Answer 10

efficient for computers but hard for people to work with

Question 11

octal is base

Answer 11

8

Question 12

hexidecimal is base

Answer 12

16

Question 13

octal and hexidecimal are more ______________ and can easily ___________

Answer 13

more compact and easily readable by people and can easily be converted into binary

Question 14

finite representation: It is important to note that in a computer system

Answer 14

There is a finite number of bits used to store numbers

Question 15

for unsigned integers, using n bits and representation as base 2 numbers can represent integers from ________ to _____

Answer 15

0 to 2^n

Question 16

sign magnitude

Answer 16

one bit for sign, and remaining bits store absolute value of number in binary

Question 17

with n bits in sign magnitude the range is

Answer 17

-((2^n -1)-1) to (2^n -1)-1

Question 18

disadvantages of sign magnitude

Answer 18

two representations of 0

hardware circuits implementing arithmetic are inefficient

Question 19

One’s complement

Answer 19

Representation of non-negatives same as unsigned

-x is x with all 0 changed to 1’s and vice versa

Question 20

One’s complement range with n bits

Answer 20

-((2^n -1) -1) to (2^n -1)-1

Question 21

Disadvantages and Advantages of one’s complement

Answer 21

two representations of zero

more efficient arithmetic operations

Question 22

Ones complement is used in _______

But is not used in __________, although it has been used for this in the past

Answer 22

internet communication when computing checksums used in packets for error detections purposes
Computer system representation of signed integers

Question 23

Current representation of signed integers used in computer systems

Answer 23

two’s complement

Question 24

Two’s complement

Answer 24

non-negative same as unsigned

negative involves changing 0’s to 1’s and 1’s to 0’s and then adding 1

Question 25

Range of two’s complement

Answer 25

-2^(n-1) to 2^(n-1)-1

Question 26

to subtract 2’s complement numbers

Answer 26

change to addition problem and get the negative

Question 27

overflow

Answer 27

When the correct result is not representable in the current number of bits

Question 28

unsigned overflow

Answer 28

overflow when operands and results represent unsigned integers

Question 29

signed overflow

Answer 29

overflow when operands and results represent signed integers

Question 30

in mips add and sub raise excpetions if ______,

and addu and subu _____

Answer 30

signed overflow occurs,

do not

Question 31

C compiler always uses

Answer 31

addu and subu

Question 32

Mips machine language is ______

Answer 32

fixed length (32 bits)

Question 33

Mips formats

Answer 33

I format
J format
R format

Question 34

op field

Answer 34

uniquely identifies the instruction type for I, J format instructions

Question 35

R format instructions have

type given in

Answer 35

0 in op field

funct field

Question 36

A bigger op field could ________, but ________

Answer 36

always uniquely identify instruction type

there is not enough bits for I and J formatting

Question 37

32 registers means that each register is

Answer 37

32 bits

Question 38

a large constant can be put in a register by

Answer 38

separately loading the value into the upper 16 bits and a value into the lower 16 bits

Question 39

16 bit values are small enough

Answer 39

to fit in the numeric constant field in the I format