Simple 8085 Programs

8085 Assembly Language Programs - For Exam

1. 8-bit Addition

Instruction	Explanation
LDA 2000H	Load first number into A
MOV B,A	Store in B
LDA 2001H	Load second number
ADD B	A = A + B
STA 2002H	Store result into memory
HLT	Stop execution

2. 16-bit Addition

Instruction	Explanation
LHLD 2000H	Load first 16-bit number into HL register pair
XCHG	Exchange HL with DE (store first number in DE)
LHLD 2002H	Load second 16-bit number into HL
DAD D	Add DE to HL (HL = HL + DE)
SHLD 2004H	Store result from HL into memory
HLT	Stop execution

3. Subtraction (8-bit)

Instruction	Explanation
LDA 2000H	Load first number into accumulator
MOV B,A	Copy first number into register B
LDA 2001H	Load second number into accumulator
SUB B	Subtract B from A (A = A - B)
STA 2002H	Store result in memory
HLT	Stop execution

4. Multiplication

Instruction	Explanation
MVI B,05H	Load multiplier into register B
MVI C,03H	Load multiplicand into register C
MVI A,00H	Clear accumulator
LOOP: ADD C	Add multiplicand to accumulator
DCR B	Decrement counter
JNZ LOOP	Repeat until B becomes zero
STA 2000H	Store result
HLT	Stop execution

5. Division

Instruction	Explanation
MVI B,03H	Load divisor into register B
LDA 2000H	Load dividend into accumulator
MVI C,00H	Initialize quotient to zero
LOOP: CMP B	Compare A with divisor
JC END	If A < B, jump to END
SUB B	Subtract divisor from A
INR C	Increment quotient
JMP LOOP	Repeat loop
END: STA 2001H	Store remainder
MOV A,C	Move quotient to accumulator
STA 2002H	Store quotient
HLT	Stop execution

6. Largest Number

Instruction	Explanation
LXI H,2000H	Load address of array
MOV C,M	Load count into register C
INX H	Point to first element
MOV A,M	Assume first element as largest
LOOP: INX H	Move to next element
CMP M	Compare with current largest
JNC SKIP	If A ≥ M skip update
MOV A,M	Update largest value
SKIP: DCR C	Decrease counter
JNZ LOOP	Repeat loop
STA 2100H	Store result
HLT	Stop execution

7. Smallest Number

Instruction	Explanation
LXI H,2000H	Load array address
MOV C,M	Load count
INX H	Point to first element
MOV A,M	Assume smallest
LOOP: INX H	Next element
CMP M	Compare values
JC SKIP	If A < M skip
MOV A,M	Update smallest
SKIP: DCR C	Decrease count
JNZ LOOP	Repeat
STA 2100H	Store result
HLT	Stop execution

8. BCD → ASCII

Instruction	Explanation
LDA 2000H	Load BCD value
ANI 0FH	Mask upper bits
ADI 30H	Add ASCII offset
STA 2001H	Store ASCII result
HLT	Stop execution

9. ASCII → BCD

Instruction	Explanation
LDA 2000H	Load ASCII value
SUI 30H	Subtract ASCII offset
STA 2001H	Store BCD result
HLT	Stop execution