Computer Architecture & Assembly Language MCQs with Answers
Practice important Computer Architecture & Assembly Language MCQs with answers and explanations.
Multiple Choice Questions
Q321: What is the purpose of the AH register in the INT 14 - SERIAL - READ CHARACTER FROM PORT service?
- A: Set baud rate
- B: Read character
- C: Line status
- D: Modem status
View Answer
C
Q322: Which port range is used to access COM1 for serial communication?
- A: 3F8-3FF
- B: 2F8-2FF
- C: 3F0-3F7
- D: 2E8-2EF
View Answer
A
Q323: What is indicated by a '101' value in the interrupt identification register?
- A: Timer interrupt
- B: Modem status interrupt
- C: Timeout interrupt
- D: Data received
View Answer
A
Q324: Which register must be set to enable interrupt generation by the serial port?
- A: 3FC
- B: 3FA
- C: 3F9
- D: 3FB
View Answer
D
Q325: What is the purpose of the line control register in serial port programming?
- A: Set modem status
- B: Set baud rate
- C: Control line status
- D: Enable interrupts
View Answer
C
Q326: In the given assembly program, what does the instruction mov ax, 0xb800 do?
- A: Clear screen
- B: Point to video memory
- C: Set baud rate
- D: Write character to port
View Answer
B
Q327: Which register holds the interrupt identification in the provided code example?
- A: 3F8
- B: 3FC
- C: 3FA
- D: 3F9
View Answer
C
Q328: What is the function of rep stosw in the code example?
- A: Receive data
- B: Transmit data
- C: Clear the screen
- D: Set baud rate
View Answer
C
Q329: Which instruction in the code sets the line settings to 9600, 8, N, 1?
- A: mov ax, 0xb800
- B: mov al, 0xE3
- C: mov dx, 0x3FA
- D: mov dx, 0x3F8
View Answer
B
Q330: What does the instruction out 0x20, al do in the context of the provided code?
- A: Initialize port
- B: Set baud rate
- C: End of interrupt
- D: Write character to port
View Answer
C