ps2kb_uart.c

meg16 的所有功能实例

/****************************************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，并且解码以后发送到串口显示。
**      
**
**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

void port_init(void)
{
	DDRD =  0Xe7;
    PORTD = 0XFF;

}

void UART_init( void )
{
	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)
{
	while(!(UCSRA&(1<<UDRE)));
	
	UDR = data;
}

void uart_trans_str(unsigned char *s)
{
 	while(*s)
	{
	 uart_transmit(*s);
	 s++;
	}
}
#pragma interrupt_handler int1_scr:3
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;
		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();
	MCUCR = 0x08;
 	GICR  = 0x80;
 	SEI();
	for(i=0;i<60000;i++)//延时
	;
	uart_transmit('\n');		
	uart_trans_str("     Welcome You!");
	uart_transmit('\n');		
	uart_trans_str("    You are the best!");	
	uart_transmit('\n');
	uart_trans_str("   EndyLu AVR 2.0");
	uart_transmit('\n');
	uart_trans_str(" PS2 Keyboard test program 1.0");	
	uart_transmit('\n');
	uart_trans_str("Please input with keyboard:");
	while(1)
	{
	
	 	if(flag ==1)
	 	{ 
		  	//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;
	    }
	} 
 }