dirkeyboard_1.c

包括直接式、矩阵式、、中断式键盘接口软件设计和键盘消抖软件设计

/**********************************************
*   File: DirKeyboard_1.C
*   Description: Direct Keyboard Interface Example
*   Created Date:  2007-10-01
*   Last Modified: 2007-10-01
*   Author: Jeffrey - [e-mail]
*   Notes: None
**********************************************/
#include <REGX51.h>

unsigned char Read_Keyboard();

/**********************************************
*   Function: delay(unsigned int t)
*   Input Variables: t
*   Return Variables: None
*   Usage: Common Delay Routine, t as the delay time ticks
**********************************************/
void delay(unsigned int t)
{
		for(;t>0;t--);		// 延时循环
}

/**********************************************
*   Function: main()
*   Input Variables: None
*   Return Variables: None
*   Usage: Program Entry
*********************************************/
void main()
{
		unsigned char Keyboard_Status;					// 定义键值
		while(1)
		{
				Keyboard_Status = Read_Keyboard();		// 读取按键值
				P0 = ~Keyboard_Status;					// 点亮相应的LED灯
				
				//********************主程序部分*********************//
				// Add your code here
				//********************主程序部分*********************//
		}
}

/**********************************************
*   Function: Read_Keyboard
*   Input Variables: None
*   Return Variables: Keys Value
*   Usage: Read Keyboard Status
*********************************************/
unsigned char Read_Keyboard()
{
		unsigned char Keys_Value;						// 定义键值变量
		P2 = 0xff;													// P2口置高，准备读取按键状态
		Keys_Value = P2;										// 读取按键状态
		return Keys_Value;									// 返回按键状态值
}