key.c

来自「程序实现LC75823驱动」· C语言 代码 · 共 36 行

#define _KEY_INCLUDE
#include "include.h"

sbit KEYIN0 = P1^3;
sbit KEYIN1 = P1^4;

void NopTime(void)
{
	BYTE i;
	for (i = 0; i < 50; i++)
			;
}

BYTE KeyScan(void)
{
	unsigned char CurrKeyNum, PreKeyNum;

	PreKeyNum = NoKey;
	while (1)
	{
		CurrKeyNum = NoKey;
		if (KEYIN0)
			CurrKeyNum = LeftKey;
		else if (KEYIN1)
			CurrKeyNum = RightKey;

		if (CurrKeyNum != NoKey)
			PreKeyNum = CurrKeyNum;
		else
			return PreKeyNum;

		NopTime();//software for key wobble
	}
}