MCQOPTIONS
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MCQOPTIONS
This section includes 2291 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 551. |
The following command will copy the accumulator to the location whose address is 23H: MOV 23H,A |
| A. | True |
| B. | False |
| Answer» B. False | |
| 552. |
The special function registers can be referred to by their hex addresses or by their register names. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 553. |
This program code will read data from port 0 and write it to port 2, and it will stop looping when bit 3 of port 2 is set: STAT: MOV A, PO MOV P2,A JNB P2.3, STAT |
| A. | True |
| B. | False |
| Answer» B. False | |
| 554. |
Which of the following commands will move the value at port 3 to register 2? |
| A. | MOV P2, R3 |
| B. | MOV R3, P2 |
| C. | MOV 3P, R2 |
| D. | MOV R2, P3 |
| Answer» E. | |
| 555. |
Which of the following instructions will load the value 35H into the high byte of timer 0? |
| A. | MOV TH0, #35H |
| B. | MOV TH0, 35H |
| C. | MOV T0, #35H |
| D. | MOV T0, 35H |
| Answer» B. MOV TH0, 35H | |
| 556. |
When the 8051 is reset and the EA line is LOW, the program counter points to the first program instruction in the: |
| A. | internal code memory |
| B. | external code memory |
| C. | internal data memory |
| D. | external data memory |
| Answer» C. internal data memory | |
| 557. |
The designs of a centigrade thermometer and a PWM speed-control circuit can be implemented by the 8051. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 558. |
This program code will be executed once: STAT: MOV A, #01H JNZ STAT |
| A. | True |
| B. | False |
| Answer» C. | |
| 559. |
Bit-addressable memory locations are: |
| A. | 10H through 1FH |
| B. | 20H through 2FH |
| C. | 30H through 3FH |
| D. | 40H through 4FH |
| Answer» C. 30H through 3FH | |
| 560. |
The last 96 locations in the internal data memory are reserved for general-purpose data storage and stack. |
| A. | True |
| B. | False |
| Answer» C. | |
| 561. |
Microcontrollers often have: |
| A. | CPUs |
| B. | RAM |
| C. | ROM |
| D. | all of the above |
| Answer» E. | |
| 562. |
The 8051 has ________ parallel I/O ports. |
| A. | 2 |
| B. | 3 |
| C. | 4 |
| D. | 5 |
| Answer» D. 5 | |
| 563. |
The 8-bit address bus allows access to an address range of: |
| A. | 0000 to FFFFH |
| B. | 000 to FFFH |
| C. | 00 to FFH |
| D. | 0 to FH |
| Answer» D. 0 to FH | |
| 564. |
The contents of the accumulator after this operation MOV A,#0BH ANL A,#2CH will be |
| A. | 11010111 |
| B. | 11011010 |
| C. | 00001000 |
| D. | 00101000 |
| Answer» D. 00101000 | |
| 565. |
The total external data memory that can be interfaced to the 8051 is: |
| A. | 32K |
| B. | 64K |
| C. | 128K |
| D. | 256K |
| Answer» C. 128K | |
| 566. |
The I/O ports that are used as address and data for external memory are: |
| A. | ports 1 and 2 |
| B. | ports 1 and 3 |
| C. | ports 0 and 2 |
| D. | ports 0 and 3 |
| Answer» D. ports 0 and 3 | |
| 567. |
The following program will receive data from port 1, determine whether bit 2 is high, and then send the number FFH to port 3: READ: MOV A,P1 ANL A,#2H CJNE A,#02H,READ MOV P3,#FFH |
| A. | True |
| B. | False |
| Answer» B. False | |
| 568. |
Device pins XTAL1 and XTAL2 for the 8051 are used for connections to an external oscillator or crystal. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 569. |
When the 8051 is reset and the line is HIGH, the program counter points to the first program instruction in the: |
| A. | internal code memory |
| B. | external code memory |
| C. | internal data memory |
| D. | external data memory |
| Answer» B. external code memory | |
| 570. |
An alternate function of port pin P3.4 in the 8051 is: |
| A. | Timer 0 |
| B. | Timer 1 |
| C. | interrupt 0 |
| D. | interrupt 1 |
| Answer» B. Timer 1 | |
| 571. |
Both registers TL0 and TL1 are needed to start Timer 0. |
| A. | True |
| B. | False |
| Answer» C. | |
| 572. |
The active switching element used in all TTL circuits is the ________. |
| A. | bipolar junction transistor (BJT) |
| B. | field-effect transistor (FET) |
| C. | metal-oxide semiconductor field-effect transistor (MOSFET) |
| D. | unijunction transistor (UJ) |
| Answer» B. field-effect transistor (FET) | |
| 573. |
An open-collector output requires ________. |
| A. | a pull-down resistor |
| B. | a pull-up resistor |
| C. | no output resistor |
| D. | an output resistor |
| Answer» C. no output resistor | |
| 574. |
Most TTL logic used today is some form of ________. |
| A. | Schottky TTL |
| B. | tristate TTL |
| C. | low-power TTL |
| D. | open-collector TTL |
| Answer» B. tristate TTL | |
| 575. |
One output structure of a TTL gate is often referred to as a ________. |
| A. | totem-pole arrangement |
| B. | diode arrangement |
| C. | JBT arrangement |
| D. | base, emitter, collector arrangement |
| Answer» B. diode arrangement | |
| 576. |
An open-drain gate is the CMOS counterpart of ________. |
| A. | an open-collector TTL gate |
| B. | a tristate TTL gate |
| C. | a bipolar junction transistor |
| D. | an emitter-coupled logic gate |
| Answer» B. a tristate TTL gate | |
| 577. |
Express the decimal number 37 as an 8-bit number in sign-magnitude. |
| A. | 10100101 |
| B. | 00100101 |
| C. | 11011000 |
| D. | 11010001 |
| Answer» B. 00100101 | |
| 578. |
When using the repeated division by 2 method of converting from decimal to binary, one must write the first remainder as the: |
| A. | MSB |
| B. | MSB, provided the following sequence of remainders are written in descending order until the final remainder is achieved. |
| C. | LSB |
| D. | LSB, provided the final remainder is used to replace the original LSB, which is then moved to the MSB position. |
| Answer» D. LSB, provided the final remainder is used to replace the original LSB, which is then moved to the MSB position. | |
| 579. |
Convert 52716 to binary. |
| A. | 343 |
| B. | 001101000111 |
| C. | 010100100111 |
| D. | 011100100101 |
| Answer» D. 011100100101 | |
| 580. |
Convert 5278 to binary. |
| A. | 011100111 |
| B. | 101010111 |
| C. | 343 |
| D. | 111010101 |
| Answer» C. 343 | |
| 581. |
The base of the hexadecimal system is: |
| A. | eight. |
| B. | sixteen. |
| C. | ten. |
| D. | two. |
| Answer» C. ten. | |
| 582. |
Assign the proper even parity bit to the code 1100001. |
| A. | 11100001 |
| B. | 1100001 |
| C. | 01100001 |
| D. | 01110101 |
| Answer» B. 1100001 | |
| 583. |
Select one of the following statements that best describes the parity method of error detection. |
| A. | Parity checking is best suited for detecting single-bit errors in transmitted codes. |
| B. | Parity checking is not suitable for detecting single-bit errors in transmitted codes. |
| C. | Parity checking is capable of detecting and correcting errors in transmitted codes. |
| D. | Parity checking is best suited for detecting double-bit errors that occur during the transmission of codes from one location to another. |
| Answer» B. Parity checking is not suitable for detecting single-bit errors in transmitted codes. | |
| 584. |
Which of the following is the primary advantage of using the BCD code instead of straight binary coding? |
| A. | Fewer bits are required to represent a decimal number with the BCD code. |
| B. | The relative ease of converting to and from decimal. |
| C. | BCD codes are easily converted to hexadecimal codes. |
| D. | BCD codes are easily converted to straight binary codes. |
| Answer» C. BCD codes are easily converted to hexadecimal codes. | |
| 585. |
How many BCD code bits and how many straight binary bits would be required to represent the decimal number 643? |
| A. | 12 BCD, 12 binary |
| B. | 12 BCD, 10 binary |
| C. | 12 BCD, 9 binary |
| D. | 16 BCD, 9 binary |
| Answer» C. 12 BCD, 9 binary | |
| 586. |
What is the decimal value of the hexadecimal number 777? |
| A. | 191 |
| B. | 1911 |
| C. | 19 |
| D. | 19111 |
| Answer» C. 19 | |
| 587. |
Convert 110010012 (binary) to decimal. |
| A. | 201 |
| B. | 2001 |
| C. | 20 |
| D. | 210 |
| Answer» B. 2001 | |
| 588. |
The American Standard Code for Information Interchange (ASCII) uses how many individual pulses for any given character? |
| A. | 1 |
| B. | 2 |
| C. | 7 |
| D. | 8 |
| Answer» D. 8 | |
| 589. |
Convert the following hexadecimal number to decimal.B516 |
| A. | 212 |
| B. | 197 |
| C. | 165 |
| D. | 181 |
| Answer» E. | |
| 590. |
The BCD number for decimal 16 is ________. |
| A. | 00010110 |
| B. | 00010000 |
| C. | 00010010 |
| D. | 11100000 |
| Answer» B. 00010000 | |
| 591. |
Convert the following hexadecimal number to decimal.1CF16 |
| A. | 463 |
| B. | 4033 |
| C. | 479 |
| D. | 4049 |
| Answer» B. 4033 | |
| 592. |
Convert the binary number 1011010 to hexadecimal. |
| A. | 5B |
| B. | 5F |
| C. | 5A |
| D. | 5C |
| Answer» D. 5C | |
| 593. |
Convert hexadecimal C0B to binary. |
| A. | 110000001011 |
| B. | 110000001001 |
| C. | 110000001100 |
| D. | 110100001011 |
| Answer» B. 110000001001 | |
| 594. |
Convert 73116 to decimal. |
| A. | 216.4 |
| B. | 985 |
| C. | 3D9 |
| D. | 1841 |
| Answer» E. | |
| 595. |
Convert the following BCD number to decimal.010101101001bcd |
| A. | 539 |
| B. | 2551 |
| C. | 569 |
| D. | 1552 |
| Answer» D. 1552 | |
| 596. |
The binary number 11001110 is equal to the decimal number ________. |
| A. | 12 |
| B. | 206 |
| C. | 127 |
| D. | 66 |
| Answer» C. 127 | |
| 597. |
The binary number for F3A16 is ________. |
| A. | 111100111010 |
| B. | 111100111110 |
| C. | 000000111010 |
| D. | 000011000100 |
| Answer» B. 111100111110 | |
| 598. |
Convert the following BCD number to decimal.100000000011bcd |
| A. | 8003 |
| B. | 803 |
| C. | 1003 |
| D. | 103 |
| Answer» C. 1003 | |
| 599. |
What is the result when a decimal 5238 is converted to base 16? |
| A. | 327.375 |
| B. | 12.166 |
| C. | 1388 |
| D. | 1476 |
| Answer» E. | |
| 600. |
The decimal number 18 is equal to the binary number ________. |
| A. | 11110 |
| B. | 10001 |
| C. | 10010 |
| D. | 1111000 |
| Answer» D. 1111000 | |