#定義uchar無符號字符
sbit key1=p1^0；
sbit key2=p1^1；
sbit key3=p1^2；
sbit key4=p1^3；
uchar LED = 0xfe
無效延遲(uchar a)
{
uchar i，j；
for(I = 0；我& lta；i++)
for(j = 0；j & lt120;j++)；
}
主()
{
P0 = 0xff
while(1)
{
while(key 1 = = 0){ P0 = 0x 00；延遲(200)；P0 = 0xff延遲(200)}
while(key 2 = = 0){ P0 = 0x ff；}
while(key 3 = = 0){ P0 = LED；LED =(LED & lt；& lt1)| 0x 01；if(LED = = 0x ff)LED = 0x Fe；延遲(200)；}
while(key 4 = = 0){ P0 = LED；LED =(LED & gt；& gt1)| 0x 80；if(LED = = 0x ff)LED = 0x7f；延遲(200)；}
}
}