keypad.c

来自「ATmegal128连接128*16的LCD模块的驱动程序」· C语言 代码 · 共 36 行

#include    <iom128.h>
#include     <ina90.h>
#include    "TypeDef.h"
#include    "keypad.h"

__farflash byte Scan2Key[19] = {1, 4, 7,10,13,16, 2, 5, 8, 0, 14,17, 3, 6, 9,12,15,18, 0};
byte KeyCheck(void);

byte KeyCheck(void)
{
	byte	i, mask, temp;

	PORTB	&= KEY_SCAN0;
	temp	= PINA;
	temp	= PINA;
	PORTB	|= KEY_NO_SCAN;
	if (temp != 0xff)
		for(i=0, mask=0x01; i<6; i++, mask<<=1)		if (!(temp&mask))	return	Scan2Key[i];

	PORTB	&= KEY_SCAN1;
	temp	= PINA;
	temp	= PINA;
	PORTB	|= KEY_NO_SCAN;
	if (temp != 0xff)
		for(i=0, mask=0x01; i<6; i++, mask<<=1)		if (!(temp&mask))	return	Scan2Key[6+i];

	PORTB	&= KEY_SCAN2;
	temp	= PINA;
	temp	= PINA;
	PORTB	|= KEY_NO_SCAN;
	if (temp != 0xff)
		for(i=0, mask=0x01; i<6; i++, mask<<=1)		if (!(temp&mask))	return	Scan2Key[12+i];

	return	NO_KEY;
}