42 lines
884 B
C
42 lines
884 B
C
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#include "directkey.h"
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#include "main.h"
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uint8_t ReadDirectKey(void) {
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static uint8_t KeyState = State0;
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static uint8_t KeyOld;
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uint8_t KeyPress;
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uint8_t KeyValue = NoKey;
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KeyPress = KeyPort->IDR & 0x000F; // 读按键
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switch (KeyState) {
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case State0:
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if (KeyPress != NoKey) {
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KeyOld = KeyPress; // 保存原来的键
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KeyState = State1; // 切换状态
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}
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break;
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case State1:
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if (KeyPress == KeyOld) {
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KeyState = State2;
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// KeyValue = KeyOld; // 按下有效
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} else {
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KeyState = State0;
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}
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break;
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case State2:
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if (KeyPress == NoKey) {
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KeyState = State0;
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KeyValue = KeyOld; // 抬起有效
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} else {
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}
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break;
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default:
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break;
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}
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return KeyValue;
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}
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