Make this year with full of joy and happiness in this world.
Let there be peace, growth and mankind with enjoyment this year.
Think always Positive to change the world.
Think Good and big to become Big.
Thanks God.
May God bless you.
Microprocessor cannot understand a program written in Assembly Language .
Instruction are divided into bit pattern of word in byte as op-code(operation code) and operation
Instruction format has three types
1.One byte-has op-code
2.Two byte- has op-code and address
3.Three byte -has code and address lower byte and address higher byte
opcode
1 byte
opcode
Data / address
2 byte
opcode
Data / address Lower byte
Data Address Higher byte
3 byte
Instructions set for 8085 are classified into five categories:
1.Data transfer group instructions
2.Arithmetic group of instrructions
3.Logical group
4.Branching group
5.Machine Level
A program known in Assembler is used to covert a Assembly language program to machine language.
I) Data transfer copy operation:-
1)Load a 8 bit number in a register
2)Copy from Register to Register
3)Copy between Register and Memory
4)Copy between Input/Output Port and Accumulator
5)Load a 16 bit number in a Register pair
6) Copy between Register pair and Stack memory
Example :-
1.Load a 8 bit number 4F in register B -MVI B ,4FH
2.Copy from Register B to Register A -MOV A,B
3.Load a 16 bit number 2050 in Register pair HL -LXI H,2050H
4.Copy from Register B to Memory Address 2050 - MOV M,B
5.Copy between Input/Output Port and Accumulator- OUT 01H IN 07H
2)Arithmetic operations and instructions
1.Add 8 bit number 32 H to Accumulator -ADI 32 H
2.Add contents of Register B to Accumulator - ADD B
3.Subtract a 8 bit number 32 H from Accumulator - SUI 32H
4.Subtract contents of Register C from Accumulator -SUB C
5.Increment the contents of Register D by 1 - INR D
6.Decrement the contents of Register E by 1 - DCR E
3)Logical and Bit Manipulation operations and instructions
1.Logically AND Register H with Accumulator -ANA H
2.Logically OR Register L with Accumulator -ORA L
3.Logically XOR Register B with Accumulator - XRA B
4.Compare contents of Register C with Accumulator -CMP C
5.Complement Accumulator -CMA
6.Rotate Accumulator Left -RAL
Program to add two 8 bit numbers and store result in register C
1.Get two numbers
a) Load first no. in register D MVI D , 2H
b)Load second no. in register E MVI E , 3H
2.Add them
a) Copy register D to A MOV A , D
b) Add register E to A ADD E
3. Store result
a)Copy A to register C MOV C , A
4.Stop
a)Stop processing HLT
Program to add 8 bit number result can be more than 8 bits i.e.with carry present
1.Get two numbers
a) Load first no. in register D MVI D , 2H
b)Load second no. in register E MVI E , 3H
2.Add them
a) Copy register D to A MOV A , D
b) Add register E to A ADD E
3. Store result
a)Copy A to register C MOV C , A
4.Carry
a)Use conditional Jump instructions JNC END
5.Change
a)Clear register B MVI B ,0H
b)Increment B INR B
