readkey.txt

通过单片机的模拟通道来处理按键的例程

BYTE GetKey1( void )
{
	BYTE	min, max,val,j;
	WORD	key_in;
	BYTE	page;
	page = ReadTW88(0xFF);
	WriteTW88(0xFF, 0x00);

	val = ReadTW88(0xCA);
	key_in = val;
	min = val; max = val;
	for ( j=0; j<17; j++ ) {
		val = ReadTW88(0xCA);
		key_in += val;
		if ( val < min ) 
			min = val;
		else if ( val > max ) 
			max = val;
	}
	key_in -= min;
	key_in -= max;

	key_in >>= 4;	// divide by 16

	WriteTW88(0xFF,page);
	return (BYTE)key_in;
}

#define	_GET_KEY2_V(X)	X = GetKey1()

BYTE ReadKey_InnerMCU()
{
	BYTE	value,byKey = 0;

	_GET_KEY2_V(g_Key_2_Value_Saved);

	value = _My_Key_Value[g_Key_2_Value_Saved];	
	g_KeyValue_Saved = g_Key_2_Value_Saved;

	return value;

}

BYTE GetKey_InnerMCU()
{
	idata BYTE val;

	val = ReadKey_InnerMCU();
	if ( val == 0 ) {
		g_RepeatKey = 0;
		g_Key = 0;
		g_KeyReady = 0;
		g_keytic = 0;
		return 0;
	}

	if ( g_Key == 0 ) {				// first pressed?
		g_Key = val;
		g_keytic++;
		return 0;
	}else if ( val != g_Key) {		// same key pressed check for repeat function
		g_RepeatKey = 0;
		g_KeyReady = 0;
		g_keytic = 0;
		return 0;
	}
	else {
		g_keytic++;
		if(g_keytic == 3){
			g_RepeatKey = 0;
			g_KeyReady = 0;
			return val;
		}
			
		if ( g_keytic < 30 ) {
			return 0;
		}else{
			g_RepeatKey = 1;
			g_KeyReady = 1;
			g_keytic = 25;
			return val;
		}
	}

}