39 lines
1.3 KiB
C
39 lines
1.3 KiB
C
// test2.c
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// 定时器1中断控制两个LED交替闪烁。设置定时器1的初值，使其每隔25ms产生一次中断。
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// 在中断服务程序中，每次中断对两个LED的状态进行切换，一个LED亮时另一个LED灭，
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// 从而实现交替闪烁
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// Timer 1 interrupt to control two LED lights to alternate.
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// Set the initial value of the timer 1 to make it produce an interrupt every 25ms.
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// In the interrupt service program,
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// switch the state of the two LED lights every time an interrupt occurs,
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// one LED light on at a time, and the other LED light off,
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// thus implementing alternating flashing.
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#include "homework6.h"
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void test2()
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{
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// Set the 38 transistors to the address.
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set38(TO_LED);
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// init the timer 1.
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TMOD = 0x9E; // set the timer 1 to mode 1.
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TH1 = 0x58; // set the timer 1 to 25ms.
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TL1 = 0x66; // set the timer 1 to 25ms.
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TR1 = 1; // start the timer 1.
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ET1 = 1; // enable the timer 1 interrupt.
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EA = 1; // enable the interrupt.
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P2 = 0xFC; // init mode: the first LED light.
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while (1) {}
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}
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void Timer1_ISR() interrupt 3
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{
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TH1 = 0x9E; // reset the timer 1.
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TH1 = 0x58; // reset the timer 1.
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P2 ^= 0x03; // switch the state of the two LED lights.
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}
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void main()
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{
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test2();
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} |