iic_test.c

单片机为meg88

//ICC-AVR application builder : 2006-10-16 下午 09:35:42
// Target : M88
// Crystal: 20.0000Mhz

#include "common.h"


void KeyScanTask1(void);
void KeyScanTask2(void);
void KeyPressedTask1(void);
void KeyPressedTask2(void);

void port_init(void)
{
	PORTB = 0x01;	   //只用PB0口，并且是输入口
	DDRB  = 0xFE;	   //0是输入
	PORTC = 0x08;	   //0000 1000//   PORTC |= 0x08; PORTC &= ~0x08;
	DDRC  = 0x08;	   //1是输出 0000 1000
	PORTD = 0x00;
	DDRD  = 0x00;
}

//TIMER0 initialize - prescale:64
// WGM: Normal
// desired value: 1mSec
// actual value:  1.000mSec (0.0%)
void timer0_init(void)
{
	TCCR0B = 0x00; //stop
	TCNT0  = 0x83; //set count
	TCCR0A = 0x00;
	TCCR0B = 0x03; //start timer
}


#pragma interrupt_handler timer0_ovf_isr:17		//TIMER0 has overflowed
void timer0_ovf_isr(void)
{
	static uint s_unLoopTimeCnt = 0;

	TCNT0  = 0x83; 								//set count
	s_unLoopTimeCnt++;
	if(s_unLoopTimeCnt > 2)
	{
		s_unLoopTimeCnt = 0;
		g_ucLoopTimeFlag = true;
	}

}

void KeyScanTask(void)
{
	static uchar s_ucKeyDitheringCnt = 0;		//avoid dithering
	static uchar s_ucKeyPressCnt = 0;			//count the sequence of the pressed key
	static uint s_undisabletime = 0;

	if(PINB & 0x01)								//if the input voltage is high
	{
		s_ucKeyDitheringCnt++;
		if(s_ucKeyDitheringCnt > 5)				//delay time 5x2=10ms;avoid dithering
		{
			s_ucKeyDitheringCnt = 0;
			if(PINB & 0x01)
				g_ucKeyPressed = true;
		}
		s_undisabletime = 0;
		PORTC |= 0x08;
	}
	else
	{
		s_ucKeyDitheringCnt = 0;
		s_undisabletime++;
		if(s_undisabletime > 30000)
		{
			s_undisabletime = 0;
			PORTC &= ~0x08;
		}

		if(g_ucKeyPressed)
		{
			s_ucKeyPressCnt++;
			if(s_ucKeyPressCnt > 3)
				{
				s_ucKeyPressCnt = 1;
				g_ucFlashEnd = false;
			}
			g_ucKeyPressed = false;
		}
	}
	g_ucKeyPressedCnt = s_ucKeyPressCnt;
}

void KeyPressedTask(void)
{
	static uint  s_unLedFlashTimeDly = 0;
	static uchar s_ucLedFlashCnt = 4;
	if(g_ucKeyPressedCnt == 1)					//press the first
		IICSendStr(0x60,g_ucTorchIICData,2);
	else if(g_ucKeyPressedCnt == 2)
		IICSendStr(0x60,g_ucLightOFFData,2);
	else if((g_ucKeyPressedCnt == 3) && (!g_ucFlashEnd))		//press the second
	{
		if(s_ucLedFlashCnt > 0)
		{
			s_unLedFlashTimeDly++;
			if(s_unLedFlashTimeDly < 50)
				IICSendStr(0x60,g_ucIledIICData,2);		//led is on
			else if(s_unLedFlashTimeDly < 100)
				IICSendStr(0x60,g_ucLightOFFData,2);	//led is off
			else
			{
				s_unLedFlashTimeDly = 0;
				s_ucLedFlashCnt--;
			}
		}
		else
		{
			s_ucLedFlashCnt = 4;
			g_ucFlashEnd = true;
			IICSendStr(0x60,g_ucFlashEnIICData,2);		//enalble flash
			IICSendStr(0x60,g_ucFlashTimerIICData,2);
			IICSendStr(0x60,g_ucFlashIICData,2);		//flash is on
		}
	}
}

//call this routine to initialize all peripherals
void init_devices(void)
{
//stop errant interrupts until set up
	CLI(); //disable all interrupts
	port_init();
	twi_init();
	timer0_init();

	MCUCR = 0x00;
	EICRA = 0x0A;	//extended ext ints
	EIMSK = 0x03;

	TIMSK0 = 0x01;	//timer 0 interrupt sources
	TIMSK1 = 0x21;	//timer 1 interrupt sources
	TIMSK2 = 0x01;	//timer 2 interrupt sources

	PCMSK0 = 0x02;	//pin change mask 0			//允许外部电平中断
	PCMSK1 = 0x02;	//pin change mask 1
	PCMSK2 = 0x00;	//pin change mask
	PCICR  = 0x03;	//pin change enable
	PRR    = 0x00;	//power controller
	SEI(); //re-enable interrupts
//all peripherals are now initialized
}

void main(void)
{
	init_devices();

	while(1)
	{
		if(g_ucLoopTimeFlag)
		{
			g_ucLoopTimeFlag = false;
//			disablechip();
			KeyScanTask();					//key scan
			KeyPressedTask();				//key process
		}
	}
}