DV31: 
CLR 	C 
MOV 	A,R3 
SUBB 	A,R7 
JC 	DV30 
SETB	OV 					
RET 
DV30:
MOV 	R2,#10H 				
DM23:
CLR	C 
MOV 	A,R5 
RLC 	A 
MOV 	R5,A 
MOV 	A,R4 
RLC 	A 
MOV 	R4,A 
MOV 	A,R3 
RLC 	A 
MOV 	R3,A 
MOV	F0,C 
CLR	C 
SUBB 	A,R7 
ANL 	C,/F0 
JC 	DM24 
MOV 	R3,A 
INC	R5 
DM24:
DJNZ	R2,DM23 
MOV 	A,R3 					
ADD 	A,R3 
JC 	DM25 
SUBB 	A,R7 
JC 	DM26 
DM25: 
INC 	R5 
MOV 	A,R5 
JNZ 	DM26 
INC 	R4 
DM26: 
CLR 	OV 
RET