Basic Assembly Language Programming Using 8085 Instruction Sets

Here are Basic Assembly Language Programming Using 8085 Instruction Sets:

Assembly language programs for the Intel 8085 microprocessor involves using its instruction set to perform various tasks.

Some are Given below:

Symbol	Hexadecimal Code		Description
AND	0xxx	8xxx	And memory word to AC
ADD	1xxx	9xxx	Add memory word to AC
LDA	2xxx	Axxx	Load memory word to AC
STA	3xxx	Bxxx	Store AC content in memory
BUN	4xxx	Cxxx	Branch Unconditionally
BSA	5xxx	Dxxx	Branch and Save Return Address
ISZ	6xxx	Exxx	Increment and skip if 0
CLA	7800		Clear AC
CLE	7400		Clear E(overflow bit)
CMA	7200		Complement AC
CME	7100		Complement E
CIR	7080		Circulate right AC and E
CIL	7040		Circulate left AC and E
INC	7020		Increment AC
SPA	7010		Skip next instruction if AC > 0
SNA	7008		Skip next instruction if AC < 0
SZA	7004		Skip next instruction if AC = 0
SZE	7002		Skip next instruction if E = 0
HLT	7001		Halt computer
INP	F800		Input character to AC
OUT	F400		Output character from AC
SKI	F200		Skip on input flag
SKO	F100		Skip on output flag
ION	F080		Interrupt On
IOF	F040		Interrupt Off

Assembly Language Program to Add Two Numbers:

Explanation:

1. ORG 2000H: Specifies the starting address of the program. Adjust it based on your memory layout.
2. Initialize data:
   • LXI H, 3000H: Load HL pair with the address of the first number.
   • MOV B, M: Move the content of the memory location addressed by HL to register B.
   • LXI H, 3001H: Load HL pair with the address of the second number.
3. Addition:
   • ADD B: Add the content of register B to the accumulator.
4. Store result:
   • LXI H, 4000H: Load HL pair with the address to store the result.
   • MOV M, A: Move the content of the accumulator to the memory location.
5. HLT: Halt the microprocessor, indicating the end of the program.
6. Data section:
   • DB 05H: Define the first number (adjust the value as needed).
   • DB 0AH: Define the second number (adjust the value as needed).

Assembly Language Program to Subtract Two Numbers:

Explanation:

1. ORG 2000H: Specifies the starting address of the program. Adjust it based on your memory layout.
2. Initialize data:
   • LXI H, 3000H: Load HL pair with the address of the minuend (the first number).
   • MOV B, M: Move the content of the memory location addressed by HL to register B.
   • LXI H, 3001H: Load HL pair with the address of the subtrahend (the second number).
3. Subtraction:
   • SUB B: Subtract the content of register B from the accumulator.
4. Store result:
   • LXI H, 4000H: Load HL pair with the address to store the result.
   • MOV M, A: Move the content of the accumulator to the memory location.
5. HLT: Halt the microprocessor, indicating the end of the program.
6. Data section:
   • DB 0AH: Define the minuend (adjust the value as needed).
   • DB 05H: Define the subtrahend (adjust the value as needed).