8051 Assembly Address Based 16 bit Addition with carry program

    ORG 0000H

                MOV DPTR, #0030H

                MOVX A, @DPTR

                MOV R0, A

                INC DPTR

                MOVX A, @DPTR

                MOV R1, A

                INC DPTR

                MOVX A, @DPTR

                MOV R2, A

                INC DPTR

                MOVX R3, A

                MOV A, R1

                ADD A, R1

                ADD A, R0

                JNC OVER1

                INC R7

OVER1:   MOV DPTR,#0090H

                MOVX @DPTR, A

                MOV A, R7

                ADD A, R2

                ADD A, R3

                JNC OVER2

                INC R6

OVER2:   INC DPTR

                MOVX @DPTR, A

                MOV A, R6

                INC DPTR

                MOVX @DPTR, A

                MOV PCON, #02H