unit 2 Assembly Language

Question 1

what is architecture?

Answer 1

the programmer’s view of a computer

Question 2

what is architecture defined by?

Answer 2

instructions set (language) and operand locations(registers and memory)

Question 3

what are instructions?

Answer 3

the words in a computer’s language

Question 4

what is an instruction set?

Answer 4

the computer’s vocabulary

Question 5

where might operands come from?

Answer 5

memory, registers, or from the instruction itself

Question 6

how does the ARM architecture represent each instruction?

Answer 6

as a 32-bit word

Question 7

microarchitecture is?

Answer 7

the specific arrangement of registers, memories, ALUs, and other building blocks to form a microprocessor

Question 8

what is assembly language?

Answer 8

the human-readable representation of the computer’s native language.

Question 9

what do assembly language instructions specify?

Answer 9

the operation to perform and the operands on which to operate

Question 10

what is a mnemonic?

Answer 10

a symbolic name for a single executable machine language instruction

Question 11

what is a source operand?

Answer 11

the variables the operation is being performed on

Question 12

what is the destination operand?

Answer 12

the operand the result is written to

Question 13

what is an example of ARM assembly code for subtraction?

Answer 13

SUB a, b, c

Question 14

what is an example of ARM assembly code for addition?

Answer 14

ADD a,b,c

Question 15

what does an instruction operate on?

Answer 15

operands

Question 16

In ADD a,b,c what are the variables?

Answer 16

operands

Question 17

where can operands be stored?

Answer 17

registers, memory, or in the instruction itself

Question 18

what is the register set or register file?

Answer 18

the 16 registers used by the ARM architecture

Question 19

The fewer the registers the___?

Answer 19

faster they can be accessed

Question 20

contents are called Immediate operands because?

Answer 20

their values are immediately available from the instruction and do not require a register or memory access

Question 21

what is the move instruction (MOV) useful for?

Answer 21

initializing register values small or large

Question 22

what is the difference between memory and register file?

Answer 22

memory is larger and slower

Question 23

what variables are kept in the register?

Answer 23

frequently used variables

Question 24

ARM architecture instructions operate exclusively on?

Answer 24

registers, so data stored in memory must be moved to before it can be processed

Question 25

Most significant byte (MSB) is?

Answer 25

on the left

Question 26

least significant byte (LSB) is?

Answer 26

on the right

Question 27

the 32-bit word address and data value are given in what number system?

Answer 27

hexadecimal

Question 28

what does the loader register instruction(LDR) do?

Answer 28

allows you to read a data word from memory into a register

Question 29

how big is a each data word?

Answer 29

4 bytes

Question 30

how much bigger is a word address than a word number?

Answer 30

4 times

Question 31

how is a memory address formed?

Answer 31

adding the contents of the base register and the offset

Question 32

what does # represent?

Answer 32

the immediate

Question 33

what is the store register instruction (STR) used for?

Answer 33

to write a data word from a register into memory

Question 34

how are byte-addressable memories organized?

Answer 34

in a big-endian or little-endian fashion

Question 35

In both big-endian and little-endian the most significant by (MSB) is where?

Answer 35

on the left and the LSB is on the right

Question 36

how are bytes numbered in big-endian?

Answer 36

starting with o at the big(most significant) end (left end).

Question 37

how are bytes numbered in little-endian?

Answer 37

starting with 0 at the little(least significant) end (right end).

Question 38

What is an example of a Register?

Answer 38

R0 " register 0)

Question 39

what are the saved registers?

Answer 39

R4-R11

Question 40

what do R4-R11 hold?

Answer 40

variables

Question 41

what are the temporary registers?

Answer 41

R0-R3 and R12

Question 42

what do R0-R3 and R12 hold?

Answer 42

intermediate values

Question 43

how many bits of precision must a constant have?

Answer 43

< 8

Question 44

how many registers can MOV use?

Answer 44

2 registers

Question 45

each data byte has a unique?

Answer 45

address

Question 46

how many bytes does a 32-bit word equal?

Answer 46

4 bytes

Question 47

a word address increments by?

Answer 47

4

Question 48

address of memory word must be multiplied by?

Answer 48

4, 2x4 = 8

Question 49

AND and BIC are useful For?

Answer 49

masking bits

Question 50

how would AND or BIC mask 0xF234012F (AND or BIC) 0x000000FF ?

Answer 50

0x0000002F

Question 51

what is ORR useful for?

Answer 51

combining bit fields

Question 52

how would ORR combine 0xF2340000 with 0x00012BC?

Answer 52

0xF23412BC

Question 53

what is the conditional flag N?

Answer 53

negative, instruction result is negative

Question 54

what is the conditional flag Z?

Answer 54

zero, instruction results in zero

Question 55

what is the conditional flag C?

Answer 55

Carry, instruction causes an unsigned carry

Question 56

what is the conditional flag V?

Answer 56

Overflow, instruction causes an overflow

Question 57

where can Conditional Mnuemonics be added to Mnuemonic like SUB?

Answer 57

the end

Question 58

what does a branch allow you to do?

Answer 58

enable out of sequence instruction execution

Question 59

what are the types of branches?

Answer 59

Branch(B) and Branch and link(BL)

Question 60

what do branches point to?

Answer 60

labels

Question 61

what is a Label?

Answer 61

an instruction location

Question 62

do branches have to be conditional?

Answer 62

no, they can be unconditional