Computer Architecture & Assembly Language MCQs with Answers
Practice important Computer Architecture & Assembly Language MCQs with answers and explanations.
Multiple Choice Questions
Q161: What does the instruction int 0x21 do in the context of the provided examples?
- A: Calls BIOS
- B: Terminates the program
- C: Starts the program
- D: Resets the CPU
View Answer
B
Q162: What is the significance of 0x30 in converting a number to its ASCII representation?
- A: Adds an integer
- B: Converts a number to its ASCII code
- C: Subtracts an integer
- D: None of the above
View Answer
B
Q163: How many rows and columns are there in the standard VGA text mode?
- A: 25 rows, 80 columns
- B: 24 rows, 80 columns
- C: 30 rows, 100 columns
- D: 20 rows, 60 columns
View Answer
A
Q164: What does the code mov ax, 0x4c00 followed by int 0x21 accomplish?
- A: Clears the screen
- B: Prints 'hello world' on screen
- C: Terminates the program
- D: Restarts the program
View Answer
C
Q165: What is the purpose of the stack in the number printing algorithm?
- A: To store the number
- B: To store the ASCII code
- C: To reverse the order of digits
- D: To add digits together
View Answer
C
Q166: In which register is the quotient stored when using DIV BL?
- A: AX
- B: BX
- C: DX
- D: AL
View Answer
D
Q167: Which instruction in 8088 is used to move a block of memory from one location to another?
- A: STOS
- B: LODS
- C: MOVS
- D: CMPS
View Answer
C
Q168: What does the REP prefix do when used with string instructions?
- A: Repeats the instruction CX times
- B: Repeats the instruction until zero flag is set
- C: Repeats the instruction until zero flag is not set
- D: Clears the direction flag
View Answer
A
Q169: Which flag controls the direction of movement for string instructions?
- A: Interrupt Flag (IF)
- B: Direction Flag (DF)
- C: Zero Flag (ZF)
- D: Sign Flag (SF)
View Answer
B
Q170: What does the LODS instruction do?
- A: Compares two blocks of memory
- B: Transfers data from a register to memory
- C: Loads data from memory to a register
- D: Stores data from a register to memory
View Answer
C