2.
ORG 0000H
JNB P1.0, GUAN
JNB P1.1, GUAN
CLR P3.0 ;点亮LED
SJMP 0000H
GUAN:
SETB P3.0 ;关闭LED
SJMP 0000
END
================================
3.
ORG 0000H
MOV PCON, #00H
MOV SCON, #50H
MOV TMOD, #20H
MOV TH1, #0FDH
MOV TL1, #0FDH
SETB TR1
MOV R0, #30H
MOV R2, #10
LP:
MOV SBUF, @R0
JNB TI, $
CLR TI
INC R0
DJNZ R2, LP
SJMP $
END