SUBSTRACTION OF TWO 8 BIT NUMBERS USING 8085

AIM 

TO PERFORM THE SUBSTRACTION OF TWO 8 BIT NUMBERS USING 8085

ALGORITHM 

1. START THE PROGRAM BY LOADING THE FIRST DATA INTO ACCUMULATOR
2. MOVE THE DATA TO A REGISTER (B REGISTER)
3. GET THE SECOND DATA AND LOAD INTO ACCUMULATOR
4. SUBTRACT THE TWO REGISTER CONTENTS
5. CHECK FOR CARRY
6. IF CARRY IS PRESENT TAKE 2'S COMPLEMENT OF ACCUMULATOR
7. STORE THE VALUE OF BORROW IN MEMORY LOCATION

8. STORE THE DIFFERENCE VALUE(PRESENT IN ACCUMULATOR) TO A MEMORY
9. LOCATION AND TERMINATE THE PROGRAM

PROGRAM

MVI C,00H             INITIALIZE C TO 00
LDA 4150               LOAD THE VALUE TO ACCUMULATOR
MOV B,A                MOVE THE CONTENT OF ACCUMULATOR TO B REGISTER
LDA 4151                LOAD THE VALUE TO ACCUMULATOR
SUB B
JNC LOOP                JUMP ON NO CARRY
CMA                          COMPLEMENT VALUE IN ACCUMULATOR
INR A                         INCREMENT VALUE IN ACCUMULATOR
INR C                         INCREMENT VALUE IN REGISTER C
LOOP : STA 4152      STORE THE VALUE OF A -REGISTER TO MEMORY ADDRESS
MOV A,C                   MOVE CONTENTS OF REGISTER C TO ACCUMULATOR
STA 4153                   STORE THE VALUE OF ACCUMULATOR MEMORY ADDRESS
HLT                            TERMINATE THE PROGRAM