Bissoy.com
Doctors Medicines MCQs Q&A

In the following 8085 program how many times (decimal) is the DCRC executed? LOOP : MVIC, 78 H DCRC JNZLOOP HLT

In the following 8085 program how many times (decimal) is the DCRC executed? LOOP : MVIC, 78 H DCRC JNZLOOP HLT Correct Answer 120

Concept:

  • MVI: More immediate 8-bit.

 

Opcode

Operand

Bytes

m-cycles

T-states

MVI

Register/memory 8-bit data

2

2/3

7T/10T

 

Description: The 8-bit data are stored in the destination register or memory.

  • DCR: Decrement source by 1.

 

Opcode

Operand

Bytes

m-cycles

T-states

DCR

Register/Memory

1

1/3

4T/10T

 

Description: The contents of the designated register/memory is discriminated by 1 and the result Is stored in the same place.

  • JNZ loop: Jump execution of program immediately at the given address if condition is true. The machine cycles and 10 T-states are consumed if condition is true while two machine cycles and 7 T-states are consumed if condition is false.
  • HLT: The microprocessor finishes executing the current instruction and halts any further execution. No. of T-state = 5T.


Analysis:

Loop: MVI C, 78 H ⇒ C = (78)H = (120)10

DCRC ⇒ Decrement value of ‘C’

JNZ loop ⇒ jump to loo libel

When c ≠ 0

HLT ⇒ stop the program

Conclusion:

[ alt="F1 Neha B 27.2.21 Pallavi D14" src="//storage.googleapis.com/tb-img/production/21/02/F1_Neha%20B_27.2.21_Pallavi_D14.png" style="width: 243px; height: 157px;">

Related Questions

Simplify the value of $$\frac{{{\text{0}}{\text{.9}} \times {\text{0}}{\text{.9}} \times {\text{0}}{\text{.9 + 0}}{\text{.2}} \times {\text{0}}{\text{.2}} \times {\text{0}}{\text{.2 + 0}}{\text{.3}} \times {\text{0}}{\text{.3}} \times {\text{0}}{\text{.3}} - {\text{3}} \times 0.9 \times {\text{0}}{\text{.2}} \times {\text{0}}{\text{.3}}}}{{{\text{0}}{\text{.9}} \times {\text{0}}{\text{.9 + 0}}{\text{.2}} \times {\text{0}}{\text{.2 + 0}}{\text{.3}} \times {\text{0}}{\text{.3}} - 0.9 \times {\text{0}}{\text{.2}} - {\text{0}}{\text{.2}} \times {\text{0}}{\text{.3}} - 0.3 \times 0.9}} = ?$$
$$\frac{{38 \times 38 \times 38 + 34 \times 34 \times 34 + 28 \times 28 \times 28 - 38 \times 34 \times 84}}{{38 \times 38 + 34 \times 34 + 28 \times 28 - 38 \times 34 - 34 \times 28 - 38 \times 28}}$$            is equal to = ?
Consider three software items: Program-X, Control Flow Diagram of Program-Y and Control Flow Diagram of Program-Z as shown below Program-X: Control Flow Diagram of Program-Y sumcal (int maxint, int value) {       int result=0, i=0;       if (value <0)       {           Value = -value;       }       while ( (i
At an Electronic Data processing unit, five out of the eight program sets P,Q,R,S,T,U,V and W are to be operated daily. On any one day, except for the first day of a month, only three of the program sets must be the ones that were operated on the previous day. The program operating must also satisfy the following conditions: 1. If program P is to be operated on a day, V can’t be operated on that day. 2. If Q is to be operated on a day, T must be one of the programs to be operated after Q. 3. If R is to be operated on a day, V must be one of the programs to be operated after R. 4. The last program to be operated on any day must be either S or U. If the program sets R and W are to be operated on the first day, which of the following could be the other program on that day?
What happens when the RET statement is executed in 8085 μp? (a) Program counter is cleared (b) Control is transferred from the subroutine to the main program (c) Returning address is loaded into the accumulator (d) Returning address is loaded into the program counter from the top of the stack The correct answer is:
A software delay subroutine is written as given below: DELAY: MVI H, 255 D   MVI L, 255 D LOOP: DCR  L   JNZ  LOOP   DCR  H   JNZ  LOOP How many times DCR L instruction will be executed?
Consider a conducting loop of radius a and total loop resistance R placed in a region with a magnetic field B thereby enclosing a flux $${\phi _0}$$ . The loop is connected to an electronic circuit as shown, the capacitor being initially uncharged.
Electromagnetic Theory mcq question image
If the loop is pulled out of the region of the magnetic field at a constant speed u, the final output voltage Vout is independent of
$$\eqalign{ & {\text{The}}\,{\text{value}}\,{\text{of}} \cr & \frac{{0.1 \times 0.1 \times 0.1 + 0.02 \times 0.02 \times 0.02}}{{0.2 \times 0.2 \times 0.2 + 0.04 \times 0.04 \times 0.04}}\,\text{is}: \cr} $$
The value of $$\left( {\frac{{0.1 \times 0.1 \times 0.1 + 0.02 \times 0.02 \times 0.02}}{{0.2 \times 0.2 \times 0.2 + 0.04 \times 0.04 \times 0.04}}} \right)$$       is :
The value of $${\text{ }}\root 3 \of {\frac{{0.2 \times 0.2 \times 0.2 + 0.04 \times 0.04 \times 0.04}}{{0.4 \times 0.4 \times 0.4 + 0.08 \times 0.08 \times 0.08}}} $$        is ?