Computer Organization

Covers digital logic gates, microprocessor architecture (8085/8086), ADC/DAC circuits, counters, encoders, multiplexers, and processor instruction sets

30 Questions Published

Questions

Question 1 Multiple Choice (Single Answer)

In which of the following logic gates, the output is OFF only when both the inputs are ON?

  1. NOT
  2. Ex-NOR
  3. NAND
  4. Half Adder
  5. Conversion Rate
Question 2 Multiple Choice (Single Answer)

In which of the following, each operand datum occupies one byte in 8086 processor?

  1. DW
  2. DB
  3. DD
  4. HLT
  5. Register Addressing Mode
Question 3 Multiple Choice (Single Answer)

In which, a latching circuit timed with the clock signal would most likely have to be connected to the IGFET gate to ensure full discharge of the capacitor when the comparator's output goes high?

  1. R-2R Ladder DAC
  2. Flash Type ADC
  3. Single Slope Integrating ADC
  4. Tracking Converter
  5. Half Subtractor
Question 4 Multiple Choice (Single Answer)

In which of the following, the output is ON only when any one of the inputs were ON, and output is OFF if both inputs are at the same logic?

  1. Step Recovery
  2. Half Adder
  3. NOT Logic
  4. Ex-NOR Logic Gate
  5. Ex-OR Logic Gate
Question 5 Multiple Choice (Single Answer)

Which of the following accepts three 1 bit inputs and generate a Sum and a Carry output?

  1. Half Adder
  2. Full Adder
  3. Half Subtractor
  4. Ex-NOR Logic Gate
  5. Tracking Converter
Question 6 Multiple Choice (Single Answer)

Which of the following flags is set to 1, if the low-order 8 bits of the result contains an even number of 1's otherwise it is cleared in 8086 processor?

  1. Overflow Flag
  2. Direction Flag
  3. Trap Flag
  4. Parity Flag
  5. X1 and X2
Question 7 Multiple Choice (Single Answer)

Which should be used to clock a latch and hold circuit such as a 74LS245 or 74LS373?

  1. Address Lines
  2. Address Data Lines
  3. Address Latch Enable
  4. Status Lines
  5. Trap
Question 8 Multiple Choice (Single Answer)

Which of the following line indicates that the 8085 micro processor is going to send data away from itself?

  1. Trap
  2. X1 & X2
  3. Address Lines
  4. HALT
  5. WRITE
Question 9 Multiple Choice (Single Answer)

Which line indicates that the 8085 micro processor is expecting data to be fed to it?

  1. MVI Group
  2. READ
  3. TRAP
  4. X1 & X2
  5. Address Lines
Question 10 Multiple Choice (Single Answer)

Which of the following logic circuits takes n inputs lines and provides pow(2,n) output lines?

  1. Encoder
  2. Demultiplexer
  3. Half Adder
  4. Decoder
  5. NOT Logic
Question 11 Multiple Choice (Single Answer)

In which circuit, if any of the input resistor is different, the input voltages would have different degrees of effect on the output and the output voltage would not be a true sum?

  1. R-2R Ladder ADC
  2. Binary Weighted Input ADC
  3. Flash Type ADC
  4. Half Adder
  5. Resolution
Question 12 Multiple Choice (Single Answer)

Which of the following instructions permit the accumulator to access groups of data bytes, as may be necessary with long precision arithmetic in 8085 processor?

  1. LDAX and STAX
  2. LXI Instruction
  3. LDA and STA
  4. ADD instructions
  5. Stack pointer
Question 13 Multiple Choice (Single Answer)

Which of the following logic circuits takes data in parallel from several sources and send the data out serially on one line in a time sequence?

  1. Demultiplexer
  2. Encoder
  3. Half Subtractor
  4. Half Adder
  5. Multiplexer
Question 14 Multiple Choice (Single Answer)

Which indicates when two numbers are equal or which number is greater than the other?

  1. Encoder
  2. Magnitude Comprartor
  3. Demultiplexer
  4. Half Adder
  5. Ex-NOR Logic Gate
Question 15 Multiple Choice (Single Answer)

Which of the following instructions provides a quick means of adding one to the contents of a register or memory location in 8085 processor?

  1. ADD Instruction
  2. ADD Immediate
  3. Increment Instruction
  4. AND Immediate
  5. LXI Instruction
Question 16 Multiple Choice (Single Answer)

Which of the following instructions provides a means of subtracting 1 from the contents of a register or a memory location in 8085 processor?

  1. Decrement Instruction
  2. Subtract Instruction
  3. Subtract Immediate
  4. AND Immediate
  5. LDA and STA
Question 17 Multiple Choice (Single Answer)

Which of the following instructions perform a logical AND function between the specified byte, either in a register or in the address contained in the H and L registers, and the contents of the accumulator?

  1. AND Immediates
  2. ADD Instructions
  3. ADD Immediates
  4. AND Instructions
  5. MVI Group
Question 18 Multiple Choice (Single Answer)

In which of the following, the highest value input digit is encoded and any other active input is ignored?

  1. Enocoder
  2. Priority Encoder
  3. Demultiplexer
  4. Half Subtractor
  5. NOT Logic Gate
Question 19 Multiple Choice (Single Answer)

In which circuit, all the flip-flops are simultaneously triggered from the same clock input?

  1. Serial-in, Serial-out Shift Register
  2. Serial in, Parallel out Shift Register
  3. Ring Counters
  4. Synchronous Counter
  5. Demultiplexer
Question 20 Multiple Choice (Single Answer)

Which of the following is used for error detection in digital codes?

  1. Sum bit
  2. Carry bit
  3. Parity bit
  4. Code Converter
  5. Gray Code
Question 21 Multiple Choice (Single Answer)

Which instructions perform inclusive Or's between the specified byte, either in a register or in the address contained in the H&L registers and the contents of the accumulator in 8085 processor?

  1. OR Instructions
  2. MVI Group
  3. ADD Instructions
  4. Ex-OR Instructions
  5. LXI Instruction
Question 22 Multiple Choice (Single Answer)

Which situates various bits to form masks or generate output data via the SOD line in 8085 processor?

  1. Interrupt Mask Bits D0, D1, D2
  2. Interrupt Enable Bit
  3. Set Interrupt Mask
  4. TRAP
  5. Halt
Question 23 Multiple Choice (Single Answer)

Which instructions perform Exclusive Or's functions between a specified byte, either in a register or in a byte contained in the address in the H&L registers, and the contents of the accumulator in 8085 processor?

  1. ADD Instruction
  2. Ex-OR Instructions
  3. OR Instructions
  4. AND Instructions
  5. LXI Instruction
Question 24 Multiple Choice (Single Answer)

Which of the following instructions compares the contents of the accumulator to a fixed value provided by the second byte of the instructions?

  1. Compare Immediate
  2. Compare Instruction
  3. Ex-OR Immediate
  4. OR Instruction
  5. AND Instruction
Question 25 Multiple Choice (Single Answer)

In which of the following circuits, the mode control may control the direction of shifting in some real devices and the data will be shifted one bit position for each clock pulse?

  1. Serial-in, Parallel-out Shift Register
  2. Ring Counter
  3. Synchronous Counter
  4. Parralel-in, Parallel-out Shift Register
  5. Latch
Question 26 Multiple Choice (Single Answer)

Which of the following flags is set to 1 if the result is zero, and 0 if the result is non zero in 8086 processor?

  1. Condition Flag OF
  2. Condition Flag DF
  3. Condition Flag TF
  4. BX
  5. Condition Flag ZF
Question 27 Multiple Choice (Single Answer)

Which instruction permits the system to examine the interrupt mask by loading into the A register a byte which defines the condition of the mask bits for the maskable interrupts in 8085 processor?

  1. Interrupt Mask Bits D0, D1, D2
  2. Interrupt Enable Bit D3
  3. Read Interrupt Mask
  4. Trap
  5. X1 & X2
Question 28 Multiple Choice (Single Answer)

In which of the following, the complement output of a ring counter is fed back to the input instead of the true output?

  1. Johnson Counter
  2. Ring Counter
  3. Serial-in, Parallel-out Shift Register
  4. Decade Counter
  5. Latch
Question 29 Multiple Choice (Single Answer)

Which instruction includes the carry flag in the circle in 8086 processor?

  1. HLT
  2. RCR
  3. DW
  4. DD
  5. TRAP
Question 30 Multiple Choice (Single Answer)

In which of the following circuits, the high-to-low transition of the comparators's output will cause the shift register to load whatever binary count is being output by the counter, thus updating the ADC circuit's output?

  1. Staircase Ramp ADC
  2. Single-slope Integrating ADC
  3. Dual Slope Integrator ADC
  4. Flash Type ADC
  5. Resolution