ps2kb_uart.c

mega16读取PS2键盘编码

/****************************************Copyright (c)**************************************************
**                               ADEmbed Development Co.,LTD.                                    
**                                 http://www.adembed.com
**--------------File Info-------------------------------------------------------------------------------
** File name:			ps2KB_UART.c
** Last modified Date:  2008-12-13
** Last Version:		1.0
** Descriptions:		ps2 test.
** 
**------------------------------------------------------------------------------------------------------
** Created by:			junbolu
** Created date:		2008-12-13
** Version:				1.0
** Descriptions:		
**
**------------------------------------------------------------------------------------------------------
** Modified by:
** Modified date:
** Version:
** Descriptions:
**
**------------------------------------------------------------------------------------------------------
**ICC-AVR application builder : 2008-12-13
**Target : M16
**Crystal: 7.3728Mhz
**SCK   ----  INT1
**DATA  ----  PD3  
**描述：读取PS2键盘编码，并且解码以后通过UART发送到串口显示。直接发送不存在按键缓冲的问题
** D7口接蜂鸣器用于标记有按键按下     
**
**涉及知识点：
**          
**          
**          
*******************************************************************************************************/

#include<iom16v.h>
#include<macros.h>
//#include"scancodes.h"

#define BAUD  9600
#define BARR  (7372800/(16*BAUD)-1)


volatile unsigned char keycode=0;
volatile unsigned char step=0;
volatile char flag=0;

static unsigned char Key_UP=0, Shift = 0;//Key_UP是键松开标识，Shift是Shift键按下标识
static unsigned char BF = 0; //标识是否有字符被收到

const unsigned char UnShifted[59][2] = {
0x1C, 'a',
0x32, 'b',
0x21, 'c',
0x23, 'd',
0x24, 'e',
0x2B, 'f',
0x34, 'g',
0x33, 'h',
0x43, 'i',
0x3B, 'j',
0x42, 'k',
0x4B, 'l',
0x3A, 'm',
0x31, 'n',
0x44, 'o',
0x4D, 'p',
0x15, 'q',
0x2D, 'r',
0x1B, 's',
0x2C, 't',
0x3C, 'u',
0x2A, 'v',
0x1D, 'w',
0x22, 'x',
0x35, 'y',
0x1A, 'z',
0x45, '0',
0x16, '1',
0x1E, '2',
0x26, '3',
0x25, '4',
0x2E, '5',
0x36, '6',
0x3D, '7',
0x3E, '8',
0x46, '9',
0x0E, '`',
0x4E, '-',
0x55, '=',
0x5D, '\\',
0x29, ' ',
0x54, '[',
0x5B, ']',
0x4C, ';',
0x52, '\'',
0x41, ',',
0x49, '.',
0x4A, '/',
0x71, '.',
0x70, '0',
0x69, '1',
0x72, '2',
0x7A, '3',
0x6B, '4',
0x73, '5',
0x74, '6',
0x6C, '7',
0x75, '8',
0x7D, '9',
};

const unsigned char Shifted[59][2] = {
0x1C, 'A',
0x32, 'B',
0x21, 'C',
0x23, 'D',
0x24, 'E',
0x2B, 'F',
0x34, 'G',
0x33, 'H',
0x43, 'I',
0x3B, 'J',
0x42, 'K',
0x4B, 'L',
0x3A, 'M',
0x31, 'N',
0x44, 'O',
0x4D, 'P',
0x15, 'Q',
0x2D, 'R',
0x1B, 'S',
0x2C, 'T',
0x3C, 'U',
0x2A, 'V',
0x1D, 'W',
0x22, 'X',
0x35, 'Y',
0x1A, 'Z',
0x45, ')',
0x16, '!',
0x1E, '@',
0x26, '#',
0x25, '$',
0x2E, '%',
0x36, '^',
0x3D, '&',
0x3E, '*',
0x46, '(',
0x0E, '~',
0x4E, '_',
0x55, '+',
0x5D, '|',
0x29, ' ',
0x54, '{',
0x5B, '}',
0x4C, ':',
0x52, '"',
0x41, '<',
0x49, '>',
0x4A, '?',
0x71, '.',
0x70, '0',
0x69, '1',
0x72, '2',
0x7A, '3',
0x6B, '4',
0x73, '5',
0x74, '6',
0x6C, '7',
0x75, '8',
0x7D, '9',
};

void port_init(void)//初始化IO口
{
	DDRD =  0Xe7;
        PORTD = 0XFF;
	

}

void UART_init( void )//初始化UART
{
	UBRRH = (unsigned char)(BARR>>8);
	UBRRL = (unsigned char)BARR;
	UCSRB = (1<<RXEN)|(1<<TXEN);
	UCSRC = (1<<URSEL)|(1<<UCSZ1)|(1<<UCSZ0);       
}

void uart_transmit(unsigned char data)//uart发送数据
{
	while(!(UCSRA&(1<<UDRE)));
	
	UDR = data;
}

void uart_trans_str(unsigned char *s)//uart发送一个字符串
{
 	while(*s)
	{
	 uart_transmit(*s);
	 s++;
	}
}

void Delay_us(unsigned int time)//延时程序用于测试标记
{
while(time--);
}

void Delay_ms(unsigned int time)
{
while(time--)
	{
	Delay_us(1000);
	}
}

#pragma interrupt_handler int1_scr:3//外部中断1中断服务函数
void int1_scr(void)
{
	step++;
	
	if(step==1)
	{
		if((PIND&0X10)==1)
		{
			step = 0;
		}
	}
	else if((step>=2)&&(step<=9))
	{	
		keycode>>=1;
		
		if((PIND&0X10)==0)
		{
			keycode|=0x00;
		}
		else 
		{
			keycode|=0x80;
		}	   
	}
	else if(step == 11)
	{
		flag = 1;//表示一帧数据接收完毕
		step = 0;
	}
}

void Decode(unsigned char ScanCode) //注意:如SHIFT+G为12H 34H F0H 34H F0H 12H，也就是说shift的通码+G的通码+shift的断码+G的断码
{
	unsigned char TempCyc;	

	if (!Key_UP)                //当键盘松开时
		{
			switch (ScanCode)
				{
					case 0xF0 :	// 当收到0xF0，Key_UP置1表示断码开始
						Key_UP = 1;
					break;

					case 0x12 :	// 左 SHIFT
						Shift = 1;
					break;

					case 0x59 :	// 右 SHIFT
						Shift = 1;
					break;

					default:						
						if(!Shift)	//如果SHIFT没按下
							{
								for (TempCyc = 0;(UnShifted[TempCyc][0]!=ScanCode)&&(TempCyc<59); TempCyc++); //查表显示
								if (UnShifted[TempCyc][0] == ScanCode) 
								    uart_transmit(UnShifted[TempCyc][1]);
							} 
						else  //按下SHIFT
							{
								for(TempCyc = 0; (Shifted[TempCyc][0]!=ScanCode)&&(TempCyc<59); TempCyc++); //查表显示
								if (Shifted[TempCyc][0] == ScanCode)
								   uart_transmit(Shifted[TempCyc][1]);
							}

					break;
				}
		}
	else
		{	
			Key_UP = 0;
			switch (ScanCode) //当键松开时不处理判码，如G 34H F0H 34H 那么第二个34H不会被处理
				{
					case 0x12 :	// 左 SHIFT
						Shift = 0;
					break;

					case 0x59 :	// 右 SHIFT
						Shift = 0;
					break;
				}
		}
	BF = 0; //标识字符处理完了
} 


void main(void)
{
    unsigned int i;
	CLI(); //disable all interrupts
 	port_init();
 	UART_init();
	 /*PORTD&=~0X80;		//低电平驱动
 	 Delay_ms(100); 	//延时0.1s
 	 PORTD|=0X80;		//高电平暂停*/
	MCUCR = 0x08;
 	GICR  = 0x80;
 	SEI();
	for(i=0;i<60000;i++)//延时
	;
	uart_transmit('\n');		
	uart_trans_str("     Welcome You!");
	 /*PORTD&=~0X80;		//低电平驱动
 	 Delay_ms(100); 	//延时0.1s
 	 PORTD|=0X80;		//高电平暂停*/
	uart_transmit('\n');		
	uart_trans_str("    You are the best!");
	 /*PORTD&=~0X80;		//低电平驱动
 	 Delay_ms(100); 	//延时0.1s
 	 PORTD|=0X80;		//高电平暂停*/
	uart_transmit('\n');
	uart_trans_str("   EndyLu AVR 2.0");
	 /*PORTD&=~0X80;		//低电平驱动
 	 Delay_ms(100); 	//延时0.1s
 	 PORTD|=0X80;		//高电平暂停*/
	uart_transmit('\n');
	uart_trans_str(" PS2 Keyboard test program 1.0");	
	 /*PORTD&=~0X80;		//低电平驱动
 	 Delay_ms(100); 	//延时0.1s
 	 PORTD|=0X80;		//高电平暂停*/
	uart_transmit('\n');
	uart_trans_str("Please input with keyboard:");
	while(1)
	{
	
	 	if(flag ==1)
	 	{   
		   PORTD&=~0X80;		//低电平驱动
 	       Delay_ms(100); 	//延时0.1s
 	       PORTD|=0X80;		//高电平暂停
		  	//uart_transmit(keycode); //发送未解码信息，了解原理时可用
		    Decode(keycode);   //键盘解码
	 		 
			keycode = 0;
			
			flag = 0;
	    }
	} 
 }