Microprocessor & Interfacing Lab Experiments

Write an assembly language program to perform different arithmetic and logical operations on 8 bit and 16 bit operations.

Sep 24 2023

Aim

Apparatus:Dyna 8085 microprocessor kit.

Program:

(a) Using Immediate Data (8 Bit):

Address	Opcode	Mnemonic	Operand	Comments
C000	3E Data1	MVI	A, Data1	Get first byte in the Accumulator
C002	06 Data2	MVI	B, Data2	Get Second byte in Register B
C004	88	ADD	B	Addition of Data1 (A) + Data2 (B). Result is saved in accumulator A.
C008	76	HLT (RST1)		Halt the program

Press Space and Enter

For results check the contents of the register A as:

Press R as DYNA85>R.

Example

Data 1	Data 2	Result
A = 2	B = 3	A = 5(Accumulator)

(b) Program to add two 8 bit numbers using data stored in memory:

Algorithm:

Save the memory location of first number (i.e. C0B1) in HL register pair.

Move first number/data into accumulator

Add the second data with accumulator

Store the result in memory location C0B3H.

Store the carry in memory location C0B4H.

Address	Opcode	Lable	Mnemonic	Operand	Comments
C000	21,B1,C0		LXI	H, C0B1 H	Get address of 1st number in H-L pair
C003	7E	Mov	A, M	Shift 1st no. in accumulator
C004	23		INX	H	Increment content of H-L Pair to point to 2nd number
			MOV	B, M	Move ^2nd no into Reg. B
C005	86		ADD	B	1 ^stno. + 2 ^nd no., result is stored in accumulator
C006	23		INX	H	Increment
C007	77		MOV	M, A	Move result at address C0B3 H
C00E	23		INX	H	Move to next location
C00F	00 36		MVI	M, 00H	Store 0 if carry is not generated
C010			JNC	Label1 (C014)
C012	01 36		MVI	M, 01H	Store 1 as carry
C014	76	Label1:	HLT	RST1	Halt

Viva Questions:

Name the important CPU registers in the 8085 microprocessor?
Which are the addressing modes of 8085?
What will be the status of carry and zero flags when instruction SUB A is executed?
What is the use of ALE pin of 8085?
What is Clock Speed ?