app.c

AVR Devolpment Board

#include "avr/io.h"
#include "util/delay.h"
#include "avr/pgmspace.h"


//#define _USE_SCAN_METHOD

#define DDRx_KEY   DDRD
#define PINx_KEY   PIND
#define PORTx_KEY  PORTD


unsigned char Get_Key()
{
	unsigned char temp=0,temp1,temp2;
	unsigned char KEY_Number;

#ifndef _USE_SCAN_METHOD	
	////////////////////////////////线反转法/////////////////////
	DDRx_KEY =0x0F;
	PORTx_KEY=0xF0;
	_delay_ms(1);
	temp1=PINx_KEY;

	DDRx_KEY =0xF0;
	PORTx_KEY=0x0F;
	_delay_ms(1);
	temp2=PINx_KEY;
	temp=(temp1&0xF0)+(temp2&0x0F);
#else
	//////////////////////////扫描法///////////////////////////////
	unsigned char i;

	DDRx_KEY  =0x0F;
	PORTx_KEY =0xF0;
	asm("nop");//
	if((PINx_KEY&0xF0)!=0xF0)
	{
		_delay_ms(5);
		if((PINx_KEY&0xF0)!=0xF0)
		{
			for(i=0;i<4;i++)
			{
				temp1 =~(1<<i);
				PORTx_KEY =temp1;
				asm("nop");//一定得加!也可加小延时。
				if((PINx_KEY & 0xF0)!=0xF0)
				{
					temp2=PINx_KEY;
					temp=(temp1 & 0x0F)+(temp2 & 0xF0);
				}
	
			}

		}
	}
#endif

	switch(temp)
	{
		case 0xEE:
			KEY_Number=0;
			break;
		case 0xDE:
			KEY_Number=1;
			break;
		case 0xBE:
			KEY_Number=2;
			break;
		case 0x7E:
			KEY_Number=3;
			break;
		case 0xED:
			KEY_Number=4;
			break;
		case 0xDD:
			KEY_Number=5;
			break;
		case 0xBD:
			KEY_Number=6;
			break;
		case 0x7D:
			KEY_Number=7;
			break;
		case 0xEB:
			KEY_Number=8;
			break;
		case 0xDB:
			KEY_Number=9;
			break;
		case 0xBB:
			KEY_Number=10;
			break;
		case 0x7B:
			KEY_Number=11;
			break;
		case 0xE7:
			KEY_Number=12;
			break;
		case 0xD7:
			KEY_Number=13;
			break;
		case 0xB7:
			KEY_Number=14;
			break;
		case 0x77:
			KEY_Number=15;
			break;
		default:
			KEY_Number=255;
			break;
	} 
	return KEY_Number;
}


const prog_char SegCode[16]={
/* Cathode common Smg display code*/
0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71}; 

unsigned char DisBuffer[8]={0,0,0,0,0,0,0,0};

void Scanf(void)
{
	unsigned char i=0;
	for(i=0;i<8;i++)
	{
		PORTB = pgm_read_byte(&SegCode[DisBuffer[i]]);
		PORTA|= (1<<PA4);
		PORTA&=~(1<<PA4);	
				
		PORTB = (1<<i);
		PORTA|= (1<<PA5);
		PORTA&=~(1<<PA5);
		

		_delay_ms(2);
	}
}

int main(void)
{
	unsigned char KeyNumber=0;
	/* Set LED and Smg LE pin and USB-pull-up pin as output , databus as output */
	DDRA |=(1<<PA4)|(1<<PA5)|(1<<PA6)|(1<<PA7); 
	DDRB  = 0xFF;

	/* Off the LED display */
	PORTB = 0xFF;
	PORTA|= (1<<PA6);
	PORTA&=~(1<<PA6);
	
	/* Enable the USB pull-up */
//	PORTA|= (1<<PA7);
//	PORTB = 0x80;
	PORTA&=~(1<<PA7);

//	PORTB= 0xff;

	while(1)
	{
		KeyNumber=Get_Key();
		if(KeyNumber!=255)
			DisBuffer[7]=KeyNumber;
		
		Scanf();
	}
	return 0;
}