8085 program to check whether the given 16 bit number is palindrome or not

In this program, we will see how to check a 16-bit number is a palindrome or not.

Problem Statement

Write the 8085 Assembly language program to check a 16-bit number is palindrome or not. The number is stored at location 8000H and 8001H.

Discussion

A number is a palindrome if the number and its reversed sequence is the number itself. For example, 5225 is a palindrome, but ABCD is not a palindrome.

In this problem, we are taking the number and store it into the HL pair. Then we are performing the reverse operation on L content. If the H and updated L value are the same, then the number is a palindrome. To check that we are doing XOR operation on H and L. When the result is 0, it is a palindrome, otherwise, it is not a palindrome.

If the number is palindrome we are storing FFH at location 8050H, and when it is not palindrome the 00H is stored at 8050H.

Input

Address	Data
…	…
8000	25
8001	52
…	…

Input

Address	Data
…	…
8000	CD
8001	AB
…	…

Flow Diagram

 

Program

Address	HEX Codes	Labels	Mnemonics	Comments
F000	2A, 00, 80		LHLD 8000H	Take the 16-bit number from memory to HL pair
F003	7D		MOV A,L	Take L to A
F004	0F		RRC	Rotate Acc four times
F005	0F		RRC
F006	0F		RRC
F007	0F		RRC
F008	AC		XRA H	XOR Acc and H
F009	3E, FF		MVI A,FFH	Load FFH into A
F00B	CA, 0F, F0		JZ STORE	If Z = 1, jump to store
F00E	AF		XRA A	Otherwise load A = 0
F00F	32, 50, 80	STORE	STA 8050H	Store result at 8050H
F012	67		HLT	Terminate the program

Output

Address	Data
…	…
8050	FF
…	…

Output

Address	Data
…	…
8050	00
…	…