MCQOPTIONS
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MCQOPTIONS
This section includes 209 Mcqs, each offering curated multiple-choice questions to sharpen your Microprocessor knowledge and support exam preparation. Choose a topic below to get started.
| 151. |
Which of the following interrupt is both level and edge sensitive? |
| A. | RST 5 5 |
| B. | INTR |
| C. | RST 7 5 |
| D. | TRAP |
| Answer» E. | |
| 152. |
When a subroutine is called, the address of the instruction following the CALL instruction is stored in/on the |
| A. | stack pointer |
| B. | accumulator |
| C. | program counter |
| D. | stack |
| Answer» E. | |
| 153. |
The general purpose registers in P are |
| A. | accessible to the user physically |
| B. | accessible to the user through instructions |
| C. | not accessible to the user |
| D. | not always accessible |
| Answer» C. not accessible to the user | |
| 154. |
In sequential circuit, output at any instant of time depends on |
| A. | only input present at that instant of time |
| B. | past output as well as present input |
| C. | only on past output |
| D. | only on past input |
| Answer» C. only on past output | |
| 155. |
Which of following logic is fastest? |
| A. | TTL |
| B. | ECL |
| C. | CMOS |
| D. | LSI |
| Answer» C. CMOS | |
| 156. |
The data bus in microprocessor based systems is used for data transfer |
| A. | between the microprocessor and I/O devices |
| B. | between the microprocessor and memory |
| C. | between I/O devices and memory |
| D. | for all the above |
| Answer» C. between I/O devices and memory | |
| 157. |
In a microprocessor based system, the stack is used to store |
| A. | program |
| B. | data |
| C. | contents of PC and registers |
| D. | none of these |
| Answer» E. | |
| 158. |
The general purpose registers in microprocessor are |
| A. | accessible to the user physically |
| B. | accessible to the user through instructions |
| C. | not accessible to the user |
| D. | not always accessible |
| Answer» C. not accessible to the user | |
| 159. |
The working of a staircase switch is a typical example of the logical operation |
| A. | OR |
| B. | NOR |
| C. | Exclusive-OR |
| D. | Exclusive-NOR |
| Answer» D. Exclusive-NOR | |
| 160. |
The TRAP interrupt mechanism of an 8085 microprocessor |
| A. | executes the RST by the hardware |
| B. | executes a NOP |
| C. | executes the instruction supplied by external device through the INTA signal |
| D. | executes an instruction from memory location 20 H |
| Answer» B. executes a NOP | |
| 161. |
An IC containing more than 100000 gates will be designated as |
| A. | LSI |
| B. | VLSI |
| C. | ULSI |
| D. | MSI |
| Answer» D. MSI | |
| 162. |
The ECL can be used to switch frequency as high as |
| A. | 1 MHz |
| B. | 100 MHz |
| C. | 500 MHz |
| D. | 1 GHz |
| Answer» E. | |
| 163. |
An AND gate has 7 input. How many words are there in its truth table? |
| A. | 7 |
| B. | 49 |
| C. | 128 |
| D. | 81 |
| Answer» D. 81 | |
| 164. |
If a logic circuit has a fan-out of 4, then the circuit |
| A. | has 4 inputs |
| B. | has 4 outputs |
| C. | can drive maximum of 4 inputs |
| D. | gives output 4 times the input |
| Answer» D. gives output 4 times the input | |
| 165. |
What is the state of signal at X? |
| A. | Don't know |
| B. | Floating |
| C. | Changing their resistance |
| D. | All High |
| Answer» B. Floating | |
| 166. |
The number of switching function of 3 variables is |
| A. | 8 |
| B. | 64 |
| C. | 128 |
| D. | 256 |
| Answer» B. 64 | |
| 167. |
The crystal frequency of 8085 microprocessor is |
| A. | 2 MHz |
| B. | 3 MHz |
| C. | 4 MHz |
| D. | 6 MHz |
| Answer» E. | |
| 168. |
An OR gate has 6 inputs. How many input words are there in its truth table? |
| A. | 6 |
| B. | 36 |
| C. | 64 |
| D. | 64,000 |
| Answer» D. 64,000 | |
| 169. |
The addressing mode used in the instruction PUSH B is |
| A. | direct |
| B. | register |
| C. | register indirect |
| D. | immediate |
| Answer» D. immediate | |
| 170. |
The clock frequency of 8085 microprocessor is |
| A. | 2 MHz |
| B. | 3 MHz |
| C. | 4 MHz |
| D. | 6 MHz |
| Answer» C. 4 MHz | |
| 171. |
The 8085 microprocessor is available in |
| A. | 14-pin DIP |
| B. | 24-pin DIP |
| C. | 40-pin DIP |
| D. | 60-pin DIP |
| Answer» D. 60-pin DIP | |
| 172. |
Identify the non-maskable interrupt from the following |
| A. | RST 7 5 |
| B. | TRAP |
| C. | RST 5 5 |
| D. | RST 6 5 |
| Answer» C. RST 5 5 | |
| 173. |
In a microprocessor based system, the stack is always in |
| A. | Microprocessor |
| B. | RAM |
| C. | ROM |
| D. | EPROM |
| Answer» D. EPROM | |
| 174. |
A carry look ahead adder is frequently used for addition because it |
| A. | is faster |
| B. | is more accurate |
| C. | uses fewer gates |
| D. | costs less |
| Answer» B. is more accurate | |
| 175. |
A microprocessor differentiates between opcode, data/ address at any time by |
| A. | the sequence in which memory contents are fetched by it |
| B. | Its internal registers |
| C. | the stack pointer |
| D. | the program counter |
| Answer» C. the stack pointer | |
| 176. |
By placing an inverter between both input of an S R flipflop, it becomes |
| A. | J K flip-flop |
| B. | D flip-flop |
| C. | T flip-flop |
| D. | Master slave flip-flop |
| Answer» C. T flip-flop | |
| 177. |
The voltage level for negative logic system |
| A. | must necessarily be negative |
| B. | must necessarily be positive |
| C. | need not be negative |
| D. | must be necessarily 0 V and 5 V |
| Answer» B. must necessarily be positive | |
| 178. |
How many 1's are present in the binary representation of |
| A. | 8 |
| B. | 9 |
| C. | 10 |
| D. | 11 |
| Answer» C. 10 | |
| 179. |
A carry look ahead adder is frequently used for addition because, it |
| A. | is faster |
| B. | is more accurate |
| C. | uses fewer gates |
| D. | less constly |
| Answer» B. is more accurate | |
| 180. |
The gate whose output is Low if and only if all the inputs are High is |
| A. | NAND |
| B. | NOR |
| C. | OR |
| D. | AND |
| Answer» B. NOR | |
| 181. |
For an input pulse train of clock period T, the delay produced by an n stage shift register |
| A. | (n 1) T |
| B. | nT |
| C. | (n + 1) T |
| D. | 2nT |
| Answer» C. (n + 1) T | |
| 182. |
How many flip-flop are needed to divide the frequency by 8? |
| A. | 4 |
| B. | 5 |
| C. | 3 |
| D. | 8 |
| Answer» D. 8 | |
| 183. |
What is the form of boolean expression AB + BC = Y? |
| A. | POS |
| B. | SOP |
| C. | K map |
| D. | Matrix |
| Answer» C. K map | |
| 184. |
A certain JK flip-flop has t |
| A. | any |
| B. | 8 |
| C. | 256 |
| D. | 10 |
| Answer» D. 10 | |
| 185. |
Which of the following is used for least power? |
| A. | TTL |
| B. | ECL |
| C. | CMOS |
| D. | All of these |
| Answer» D. All of these | |
| 186. |
The supply voltage permissible for CMOS devices is |
| A. | + 5 V |
| B. | 5 V |
| C. | 3 to 15 V |
| D. | + 12 V |
| Answer» D. + 12 V | |
| 187. |
The switching speed of ECL is very high, because |
| A. | transistors are switched between cut-off and saturation regions |
| B. | transistors are switched between active and saturation region |
| C. | transistors are switched between active and cut-off regions |
| D. | transistors may operate in any of three region |
| Answer» D. transistors may operate in any of three region | |
| 188. |
In ECL negative supply voltage is used because of |
| A. | reduction in noise at the output means increase in CMRR |
| B. | saving in power |
| C. | eace of wired-OR operation |
| D. | increase speed |
| Answer» B. saving in power | |
| 189. |
For a MOD-12 counter, the Flip-Flop has a tpd = 60 ns. The NAND gate has a tpd of 25 ns. The maximum clock frequency is given by |
| A. | 37 74 MHz |
| B. | 377 4 MHz |
| C. | 3 774 MHz |
| D. | None of these |
| Answer» D. None of these | |
| 190. |
CMOS logic consists of |
| A. | only n-channel MOS devices |
| B. | only p-channel MOS devices |
| C. | equal number of n-channel and p-channel MOS devices |
| D. | None of these |
| Answer» D. None of these | |
| 191. |
Implement Y = A + |
| A. | 4 |
| B. | 6 |
| C. | 5 |
| D. | 3 |
| Answer» B. 6 | |
| 192. |
Minimum number of 2-input NAND gates required to implement the function F = ( |
| A. | 2 |
| B. | 4 |
| C. | 6 |
| D. | 5 |
| Answer» C. 6 | |
| 193. |
The number of bits needed to encode all letters (i.e., 26), 10 symbols and all number (i.e.,10) is |
| A. | 5 |
| B. | 7 |
| C. | 6 |
| D. | 8 |
| Answer» D. 8 | |
| 194. |
A 4 bit synchronous counter uses flip-flop with propagation delay time of 25 ns each. The maximum possible time required for change of state will be |
| A. | 25 ns |
| B. | 50 ns |
| C. | 75 ns |
| D. | 100 ns |
| Answer» E. | |
| 195. |
Convert (205) |
| A. | CD |
| B. | DC |
| C. | 8A |
| D. | 12E |
| Answer» B. DC | |
| 196. |
How many NAND gates are required to make A |
| A. | 8 |
| B. | 6 |
| C. | 4 |
| D. | 5 |
| Answer» D. 5 | |
| 197. |
The decimal equivalent of hexadecimal number E5 is |
| A. | 279 |
| B. | 229 |
| C. | 427 |
| D. | 3000 |
| Answer» C. 427 | |
| 198. |
The resolution of an 8 bit A/D converter is |
| A. | 0 01% |
| B. | 0 028% |
| C. | 0 024% |
| D. | 0 40% |
| Answer» E. | |
| 199. |
The widely used code in data communication is |
| A. | 8 bit ASCII |
| B. | 7 bit ASCII |
| C. | EBCDIC |
| D. | None of these |
| Answer» C. EBCDIC | |
| 200. |
In a dual slope ADC, to eliminate 50 Hz pick up, the minimum period of integration of the input signal is adjusted to be ms. |
| A. | 10 ms |
| B. | 16 67 ms |
| C. | 24 5 ms |
| D. | 36 ms |
| Answer» C. 24 5 ms | |