38 lines
665 B
C
38 lines
665 B
C
// test5.c
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// 数码管静态显示秒表的倒计时；
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#include "homework4.h"
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unsigned char cnt = 0; // 定时器溢出计数
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unsigned char second = 0; // 秒计数
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void test5()
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{
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set_38_2SEG();
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TMOD = 0x01;
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TH0 = 0x3C;
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TL0 = 0xB0;
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TR0 = 1;
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// 初始化时立即显示9
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second = 9;
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show_number(second);
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while (1) {
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if (TF0 == 1) {
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TF0 = 0;
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TH0 = 0x3C;
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TL0 = 0xB0;
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if (++cnt >= 20) {
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cnt = 0;
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second = (second > 0) ? --second : 9;
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show_number(second);
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}
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}
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}
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}
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void main()
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{
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test5();
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} |