Computer Architecture & Assembly Language MCQs with Answers
Practice important Computer Architecture & Assembly Language MCQs with answers and explanations.
Multiple Choice Questions
Q181: Which register is used to hold the value when using the STOS instruction to store data?
- A: SI
- B: DI
- C: AL or AX
- D: CX
View Answer
C
Q182: What is the purpose of the printstr subroutine?
- A: To calculate string length
- B: To print a string to the screen
- C: To clear the screen
- D: To compare two strings
View Answer
B
Q183: What register does the strlen subroutine use to return the length of the string?
- A: BX
- B: CX
- C: AX
- D: DX
View Answer
C
Q184: How does the scrollup subroutine handle the screen's data?
- A: Moves data from the bottom to the top of the screen
- B: Moves data from the top to the bottom of the screen
- C: Moves data from left to right
- D: Moves data from right to left
View Answer
A
Q185: What does the cmp cx, ax instruction do in the strcmp subroutine?
- A: Compares the length of two strings
- B: Compares the content of two strings
- C: Compares the attributes of two strings
- D: Compares the segment registers
View Answer
A
Q186: In the scrollup subroutine, which register is used to hold the number of lines to clear?
- A: AX
- B: BX
- C: CX
- D: DX
View Answer
C
Q187: How does the LES instruction operate?
- A: Loads ES and DS from memory
- B: Loads DS and ES from memory
- C: Loads DS and SI from memory
- D: Loads ES and DI from memory
View Answer
D
Q188: What is the result if the strings compared by strcmp are different?
- A: AX is set to 1
- B: AX is set to 0
- C: The program halts
- D: No change in AX
View Answer
B
Q189: What is the main advantage of using REP MOVSB for screen scrolling?
- A: It uses less memory
- B: It minimizes the time required for scrolling
- C: It simplifies the code
- D: It increases the CPU usage
View Answer
B
Q190: What is the function of the cld instruction in the printstr subroutine?
- A: Clears the screen
- B: Sets the direction flag to auto-increment
- C: Loads a value into a register
- D: Compares two strings
View Answer
B