MCQOPTIONS
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MCQOPTIONS
This section includes 8 Mcqs, each offering curated multiple-choice questions to sharpen your 8051 Microcontroller knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
How many pins of the 8255 can be used as the I/O ports? |
| A. | 8 |
| B. | 16 |
| C. | 24 |
| D. | 32 |
| Answer» D. 32 | |
| 2. |
What is correct about the BSR mode from below? |
| A. | it is active low input used to select the individual bits of the PORTA |
| B. | it is active low input used to select the individual bits of the PORTB |
| C. | it is active low input used to select the individual bits of the PORTC |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 3. |
Why MOVX instruction is being used to access the ports of the 8255? |
| A. | because 8255 is used to access the memory mapped I/O |
| B. | because 8255 is used to access the external communication |
| C. | because 8255 is used to access the data transfer |
| D. | because 8255 is used to access the interfacing of LCD, motor etc |
| Answer» B. because 8255 is used to access the external communication | |
| 4. |
What is the value of the control register when RESET button is set to zero? |
| A. | 0x00H |
| B. | 0xFFH |
| C. | 0x11H |
| D. | value remains the same as was before the RESET button was set to zero |
| Answer» E. | |
| 5. |
Which pins are used to select the ports and the control register? |
| A. | CS |
| B. | A1 |
| C. | A0 |
| D. | All of the mentioned |
| Answer» E. | |
| 6. |
Find the control word for PA= out, PB= in, PCL=out, PCH=out (Mode0)? |
| A. | 0xF0H |
| B. | 0xF2H |
| C. | 0xF4H |
| D. | 0xFFH |
| Answer» C. 0xF4H | |
| 7. |
Which pins of a microcontroller are directly connected with 8255? |
| A. | RD |
| B. | WR |
| C. | D0-D7 |
| D. | all of the mentioned |
| Answer» E. | |
| 8. |
What is the function of 8255 chip? |
| A. | the ports of 8255 can act as the input/ output port for the microcontroller |
| B. | it is a type of an internal memory device that is being interfaced with the microcontroller |
| C. | all of the mentioned |
| D. | none of the mentioned |
| Answer» B. it is a type of an internal memory device that is being interfaced with the microcontroller | |