8085 program to check whether both the nibbles of 8 bit number are equal or not

Here we will see how to check whether two nibbles of a number are same or not.

Problem Statement

Write 8085 Assembly language program to check whether upper nibble and lower nibbles are same or not.

Discussion

To check the nibbles, we have to mask at first. So we need to mask the lower nibble and upper nibble and store them into different registers. The upper nibble will be shifted to the right four bits to make it lower nibble. Then we can check both are same or not. If they are same store 00 at F150 location, otherwise store FF at F150 location.

Input

Address	Data
F050	FE

Address	Data
F050	AA

Flow Diagram

program

Address	HEX Codes	Labels	Mnemonics	Comments
F000	3A, 50 F0		LDA F050	memory element of F050
F003	47		MOV B, A	Load A into B
F004	E6, 0F		ANI 0F	Mask upper nibble
F006	4F		MOV C, A	Load C with A
F007	78		MOV A, B	Load A with B
F008	E6, F0		ANI F0	Mask lower nibble
F00A	07		RLC	Rotate A to the left
F00B	07		RLC	Rotate A to the left
F00C	07		RLC	Rotate A to the left
F00D	07		RLC	Rotate A to the left
F00E	B9		CMP C	Compare C and A
F00F	CA, 17, F0		JZ LABEL	If Z flag is enabled jump to Label
F012	3E, FF		MVI A, FF	Load A with FF
F014	C3, 19, F0		JMP STORE	Jump to Store
F017	3E, 00	LABEL	MVI A, 00	Load A with 00H
F019	32, 50, F1	STORE	STA F150	Store result at memory F150
F01C	76		HLT	Terminate the program