movi
a
dj
zbegi
callmov
dx300hal00hdxaldx303hal0chdxaldx302haldxal04hwait1ledflashbx200
LED全灭
关闭SPK
查SW3按下？PC20？
未按下，等待已按下，调用LED发光子程
movt0ffffhhiso
calldecj
zmovmovoutmovmovloso
calloutspkbxhiso
dx300hal00hdxalbx200t0afhoutspk调用喇叭发声子程（低频）LED全灭调用喇叭发声子程（高频）
fdecj
zcallmovi
tcmpjejmpquitmovmovoutmovmovoutmovi
tsle
dp
bxloso
delay2ah0bh21hal0ffhquitbegi
dx300hal00hdxaldx303hal0chdxalah4ch21h返回DOS关闭SPK有任意键按下，退出无任意键按下，继续LED全灭查任意键按下？
delay1procpushmovbxbxt
延时子程1
fdl1
decj
zpopret
bxdl1bx
delay1e
dp
delay2procpushpushmovdl4dl3movdecj
zdecj
zpoppopretdelay2e
dpcxbxcx04ffhbx0ffffhbxdl3cxdl4bxcx
延时子程2
foutspkprocmovdx303hmoval0dhoutdxalcalldelay1movdx303hmoval0choutdxalcalldelay1retoutspke
dp
喇叭发声子程从PC6输出方波置PC61
置PC60
ledflash
procmovsioffsetdata7
LED发光子程序LED的点亮代码
addsi
ummovalsimovdx300houtdxali
c
umcmpj
e
um08h
ext从8255的A口输出LED点亮代码
mov
um00h
f
extledflash
rete
dp
codee
dse
dstart
fr