FILTER3:
MOV 	R2,#04H				
SRT:
MOV 	A,R2					
MOV 	R3,A
MOV 	R0,#SAMP				
LOOP:
MOV	A,@R0				
INC 		R0
MOV 	R1,A
CLR 	C
SUBB 	A,@R0
MOV 	A,R1
JC 		DONE
MOV 	A,@R0				
DEC 	R0
XCH 	A,@R0
INC 		R0
MOV 	@R0,A
DONE:
DJNZ	R3,LOOP				
DJNZ 	R2.,SORT				
INC 		R0
MOV 	A，@R0
RET
SAMP 	EQU 30H