FDD1:
MOV B,A
MOV R2,#0
MOV A,R7
DEC A
MOV R3,A
FD61:
CLR C
MOV A,R3
SUBB A,R2
JC FD69
RRC A
ADD A,R2
MOV R4,A
MOVC A,@A+DPTR
CJNE A,B,FD65
CLR OV
MOV A,R4
RET
FD65:
JC FD68
MOV A,R4
DEC A
MOV R3,A
SJMP FD61
FD68:
MOV A,R4
INC A
MOV R2,A
SJMP FD61
FD69:
SETB OV
RET