ps2_key._c

meg16 的所有功能实例

/****************************************Copyright (c)**************************************************
**                               ADEmbed Development Co.,LTD.                                    
**                                 http://www.adembed.com
**--------------File Info-------------------------------------------------------------------------------
** File name:			ps2_key.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，没有经过任何处理直接通过串口
**      
**
**涉及知识点：
**          
**          
**          
*******************************************************************************************************/


#include<iom16v.h>
#include<macros.h>

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

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



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;

}


#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 main(void)
{

	CLI(); //disable all interrupts
 	port_init();
 	UART_init();
	MCUCR = 0x08;
 	GICR  = 0x80;
 	SEI();
 
	while(1)
	{
	 	if(flag ==1)
	 	{
	 		uart_transmit(keycode);
			
			keycode = 0;
			
			flag = 0;
	    }
	} 
 }