8051 Program to add two 16 bit Numbers (AT89C51) Microcontroller

;   8051 ASSEMBLY CODE -- CODESEXPLORER BLOG
; ALP TO ADD TWO 16 BIT NUMBER
; BELOW CODE ADDS AB20H + 65DE = 110FE WITH CARRY FLAG SET 

ORG 0000H
CLR C     ;MAKE CY=0
MOV A,#020H  ;LOWER BYTE OF OPERAND 1 IN A
ADD A,#0DEH  ;ADD LOWER BYTE OF OPERAND 2 WITH A
MOV R1,A  ;STORES LSB OF RESULT IN R1
MOV A,#65H  ;HIGHER BYTE OF OPERAND 2 IN A
ADDC A,#0ABH ; ADD WITH HIGHER BYTE OF OPERAND 1
MOV R0,A  ;STORES MSB OF RESULT IN R0
END

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addition of two 16 bit numbers  ASM File