Question

1. What instruction is used to return from a subroutine?
a) RTS
b) RTS and Pull
c) End and Pull
d) End

Answer 1

2. Suppose that the data in memory locations $7000 - $7005 are as follows:
$24, $3A, $E5, $22, $08, $41
After running the following code, specify the contents of index register x and accumulator A (ACCA).
LDX #$7002
INX
LDAA 2, X
INX
WAI

a) Content of index register X = $7004, ACCA = $41
b) Content of index register X = $7002, ACCA =$22
c) Content of index register X = $7006, ACCA =$41
d) Content of index register X = $7005, ACCA =$08

Answer 2

3. After running the following program, what is the content of SP register?
LDS #$1000
PSHB
PULA
INCB
PSHB
INCA
PSHB

a) $1002
b) $00FFE
c) $1000
d) $0FFF

Answer 3

4. After running the following assembly code, what is the content of index register X and accumulator B (ACCB)?
ORG $5000
BUFFER: dc.b $12, $77, $4C, $3E, $2A, $55
LDX #BUFFER
INX
INX
LDAB 2, X
WAI

a) Content of index register X = $5004, ACCB = $5C
b) Content of index register X = $5002, ACCB = $3E
c) Content of index register X = $5002, ACCB = $2A
d) Content of index register X = $5004, ACCB = $2A

Answer 4

5. Which of the following happens when call JSR?
a) Pushing PC to stack and then incrementing PC
b) Pulling PC from the stack and then decrementing PC
c) Pulling PC from the stack
d) Pushing PC to stack

Answer 5

6. What are the contents of the accumulator A and accumulator B after this program?
ORG $6000
ARRAY: dc.b $11,$22, $33,$44,$55,$66
LDX #ARRAY
LDAA 2,X
PSHA
LDAA 3,X
PSHA
PULA
PULB
WAI

a) ACCA=$44, ACCB = $33
b) ACCA=$55, ACCB = $44
c) ACCA=$33, ACCB = $44
d) ACCA=$44, ACCB = $55

Answer 6

7. After running the following code, what is the content of the memory address $7000?
LDAA #$01
LDAB #$02
JSR MYSUB1
ABA
JSR MYSUB2
STAA $7000
WAI
MYSUB1: TAB
RTS
MYSUB2: ASLA
RTS

a) 6
b) 2
c) 5
d) 4

Answer 7

8. In the following code, what is the address from which Accumulator B is loaded?
LDX#$22FC
INX
LDAB $21, X

a) $231F
b) $22FF
c) $231E
d) $22FE

Answer 8

9. Which of the following CodeWarrior directives is used to reserve one byte memory for variables?
a) dw.b
b) ds.b
c) dl.b
d) dc.b

Answer 9

10. After running the following code, what is the content of the memory address $7000?
LDAA #$04
LDAB #$01
JSR SUB
ABA
STAA $7000
WAI
SUB: ASRA
ADDA #$01
RTS

a) 6
b) 5
c) 3
d) 4

Answer 10

a) RTS

Answer 11

b) Content of index register X = $7002, ACCA =$22

Answer 12

a) $1002

Answer 13

c) Content of index register X = $5002, ACCB = $2A

Answer 14

d) Pushing PC to stack

Answer 15

c) ACCA=$33, ACCB = $44

Answer 16

d) 4

Answer 17

c) $231E

Answer 18

d) dc.b

Answer 19

a) 6