程序部分
& w0 K& ]: R! ?, v$ V. ^#include <reg51.h>( J+ ~/ W: ?# M% b4 }. a* [, I
void delay (unsigned int i)" u# s+ n# J4 t, ]
{
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for (k=0;k<i;k++);, w: W# F7 s4 U9 [2 A
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void main()
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unsigned char aa,i;( q. B9 h$ r' V4 S
while(1): ]( U3 U8 V: m/ ~+ \$ v4 \
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aa=0x80;! v! X ?& K+ c6 P+ [
for(i=0;i<8;i++). z: o% @9 Y O9 d
{
4 [' t6 u# N9 O4 VP1=aa;
0 U: ~- [" ^) d2 m! vdelay(25000); T$ g) V) t0 M; `" [- b7 O, m! j
aa>>=1;//左移9 q" b3 q/ g; z: S% u
}
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