MCQOPTIONS
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MCQOPTIONS
This section includes 7 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. |
Key press detection and Key identification are: |
| A. | the same processes |
| B. | two different works are done in Keyboard Interfacing |
| C. | none of the mentioned |
| D. | any of the mentioned |
| Answer» C. none of the mentioned | |
| 2. |
To identify that which key is being pressed, we need to: |
| A. | ground all the pins of the port at a time |
| B. | ground pins of the port one at a time |
| C. | connect all the pins of the port to the main supply at a time |
| D. | none of the mentioned |
| Answer» C. connect all the pins of the port to the main supply at a time | |
| 3. |
If we need to operate a key of a keyboard in an interrupt mode, then it will generate what kind of interrupt? |
| A. | ES |
| B. | EX0/EX1 |
| C. | T0/T1 |
| D. | RESET |
| Answer» C. T0/T1 | |
| 4. |
In reading the columns of a matrix, if no key is pressed we should get all in binary notation |
| A. | 0 |
| B. | 1 |
| C. | F |
| D. | 7 |
| Answer» C. F | |
| 5. |
To detect that in which column, the key is placed? |
| A. | we can mask the bits and then check it |
| B. | we can rotate the bits and then check that particular bit which is set or reset(according to the particular condition) |
| C. | none of the mentioned |
| D. | all of the mentioned |
| Answer» E. | |
| 6. |
What is described by this command: CJNE A,#00001111b, ROW1 |
| A. | it masks the bit and then jumps to the label where ROW1 is written |
| B. | it makes the value of the accumulator 0FH and then jumps at the address where ROW1 label is written |
| C. | it compares the value of the accumulator with 0FH and jumps to the location where ROW1 label is there if the value becomes equal |
| D. | it compares the value of the accumulator with 0FH and jumps to the location where ROW1 label is there if the value is not equal |
| Answer» E. | |
| 7. |
Which of the following steps detects the key in a 4*4 keyboard matrix about the key that is being pressed? |
| A. | masking of bits |
| B. | ensuring that initially, all keys are open |
| C. | checking that whether the key is actually pressed or not |
| D. | all of the mentioned |
| Answer» E. | |