//FILENAME:	DC_Motor.c
//AUTHOR:	Nate Bassett
//DESCRIPTION:	Prelab #7, Fall 2005
//	This program collects data for different tachometer speeds of a motor
//	and stores them to an array. The tachometer values are read in on
//	PA0.


#include <avr/io.h>
#include <avr/signal.h>
#include <avr/interrupt.h>
#include "sio.c"

/* ---------------Deadband Limits-------------------*/

#define c_kinetic_pos	0x02	//Static Friction
#define c_kinetic_neg	0x02	//Make the value positive
#define c_static_pos	0x04	//Kinetic Friction
#define c_static_neg	0x04	//Make the value positive
#define c_max		255	//Limit count
#define c_min		255	//Make the value positive

#define UBRR_VALUE	51	//Change to correct baud rate
#define CLK_ms		10	//Set the updates for every 10ms, same as CLK_ms



/*-------------Function Prototypes-----------------*/

int deadband(int c_wanted);
void PWM_init();
void PWM_update(int value);
void PWM_setup();
int v_output(int v_adjusted);
void IO_setup();
void IO_update();
unsigned AD_read();
void AD_setup();
int arraymaker();

/*------------------Global Variables----------------------*/

int db_correct = 0;	//Deadband correction is off by default
int j = 0;
int moving = 0;		//Assume it starts without moving
int count = 0;		//A count value to be output on Port B
int table[100];



/*-----------------------Clock Interrupt Stuff----------------------------*/

unsigned int CNT_timer1; //the delay time
volatile unsigned int CLK_ticks = 0; //the current number of ms
volatile unsigned int CLK_seconds = 0; //the current number of seconds

SIGNAL(SIG_OVERFLOW0)	//the interrupt calls this function
{
	CLK_ticks += CLK_ms;
	if(CLK_ticks >= 1) //the number of interrupts between output changes
	{
		CLK_ticks = CLK_ticks - 1;
		CLK_seconds++;
		IO_update();
	}
	TCNT0 = CNT_timer1;
}

void CLK_setup()	//start the interrupt service routine
{
	TCCR0 = (0<<FOC0) | (0<<WGM01) | (0<<WGM00) | (0<<COM00) | (0<<COM01) | (1<<CS02) | (0<<CS01) | (1<<CS00);
	//use CLK/1024 prescale value
	//disable PWM and Compare Output Modes
	CNT_timer1 = 0xFFFF - CLK_ms * 8; //8 = 1ms, 80 = 10ms
	TCNT0 = CNT_timer1; //start at the right point

	TIFR |= (1<<TOV0);
	TIFR &= ~(0<<OCF0);
	TIFR = (0<<OCF2) | (0<<TOV2) | (0<<ICF1) | (0<<OCF1A) | (0<<OCF1B) | (0<<TOV1) | (0<<OCF0) | (0<<TOV0); //set to use overflow interrupts
	TIMSK |= (1<<TOIE0);
	TIMSK &= ~(0<<OCIE0);
	TIMSK = (0<<OCIE2) | (0<<TOIE2) | (0<<TICIE1) | (0<<OCIE1A) | (0<<OCIE1B) | (0<<TOIE1) | (0<<OCIE0) | (1<<TOIE0); //Enable TCNT1 overflow
	sei(); //enable interrupts flag
}

/* Call this routine when updating */
int deadband(int c_wanted)
{
	int c_pos;
	int c_neg;
	int c_adjusted;

	if(moving == 1)
	{
		c_pos = c_kinetic_pos;
		c_neg = c_kinetic_neg;
	}
	else
	{
		c_pos = c_static_pos;
		c_neg = c_static_neg;
	}
	if(c_wanted == 0) //Turn off the output
	{
		c_adjusted = 0;
	}
	else if(c_wanted > 0) //A positive output
	{
		c_adjusted = c_pos + (unsigned)(c_max - c_pos) * c_wanted / c_max;
		if(c_adjusted > c_max)
			c_adjusted = c_max;
	}
	else //The output value must be negative
	{
		c_adjusted = -c_neg - (unsigned)(c_min - c_neg) * -c_wanted / c_min;
		if(c_adjusted < -c_min)
			c_adjusted = -c_min;
	}

	return c_adjusted;
}

void PWM_setup()
{
	DDRD = 0xFF;				//Set as an output on PD7
	TCCR2 = _BV(WGM21) | _BV(WGM20) | _BV(COM21) | _BV(CS20);
	OCR2 = 0x00;				//Set the initial duty cycle to 100%
}

//Call this routine once the program starts
void PWM_init()
{
	DDRD |= (1 << PD5);			//Set PWM outputs
	DDRC |= (1 << PC0) | (1 << PC1);	//Set motor direction outputs on Port C

	//Using OCR1
	TCCR1A = _BV(COM1A1) | _BV(COM1B1) | _BV(WGM10);	//Turn on both PWM outputs on counter 1
	TCCR1B = _BV(CS11);	//Set the internal clock to /8
}

//To update the PWM output
void PWM_update(int value)
{
	if(value > 255)
		value = 255;
	if(value < 0)
		value = 0;

	OCR2 = value;	//duty cycle
}

//Call the interrupt loop
int v_output(int v_adjusted)
{
	int RefSignal;		//The value to be returned

	if(v_adjusted >= 0)
	{
		//Set the direction bits to CW on, CCW off
		PORTC = (PINC & 0xFC) | 0x02;	//bit 1 on, 0 off
		if(v_adjusted > 255) //clip output over maximum
		{
			RefSignal = 255;
		}
		else {RefSignal = v_adjusted;}
	}
	else
	{
		//Need to reverse output sign
		//Set the direction bits to CW off, CCW on
		PORTC = (PINC & 0xFC) | 0x01;	//bit 0 on, 1 off
		if(v_adjusted < -255)	//clip output below minimum
		{
			RefSignal = 255;
		}
		else
		{
			RefSignal = -v_adjusted; //Flip sign
		}
	}

	return RefSignal;
}

void IO_setup()
{
	DDRB = 0xFF; //all of port B is outputs
	PWM_setup();
	AD_setup();
	DDRA = (unsigned char)0; //set port A to outputs
}

//This routine will run once per interrupt for updates
void IO_update()
{
	if(db_correct == 0)
		PWM_update(count);
	else
		PWM_update(deadband(count));

	if(count > 0)
		arraymaker();
}

int arraymaker()
{
	table[j] = AD_read();
	j++;
	if(j > 99)
	{
		j=0;
		count=0;
		moving=0;
	}
	return 0;
}

void AD_setup()
{
	ADMUX = 0xC0; 	//set the input to channel 0
	ADCSRA = 0xE0; 	//turn on ADC and set to free running
}

unsigned AD_read()
{
	return (ADCW >> 2);	//Returns digital output from AD register
}

void delay(int ticks) //Ticks are approx. 1 ms
{
	volatile int i,j;
	
	for(i=0;i<ticks;i++) {
		for(j=0;j<1000;j++) {}
	}
}

/* ----------------------MAIN-----------------------------*/
int main(void)
{
	int c;	
	sio_init();
	IO_setup();
	CLK_setup();

	for(;;)
	{
		while((c=input()) == -1) {}	//Wait for keypress

		if(c == '+')			//Increment the output on Port B
		{
			if(++count > 255) count = 255;
			if(count ==1)		//It has just started moving
			{
				moving = 0;
				IO_update();
				delay(200);
				moving = 1;
			}

			outint(count); outln(" = count, INCREMENTED");
		}
		else if(c == '-')
		{
			if(--count < -255) count = -255;
			if(count == -1)		//It has just started moving
			{
				moving = 0;
				IO_update();
				delay(200);
				moving = 1;
			}

			outint(count); outln(" = count, DECREMENTED");
		}
		else if(c == '0')
		{
			count = 0;
			outint(count); outln(" = count");
		}
		else if(c == '1')
		{
			count = 28;
			outint(count); outln(" = count");
		}
		else if(c == '2')
		{
			count = 56;
			outint(count); outln(" = count");
		}
		else if(c =='3')
		{
			count = 84;
			outint(count); outln(" = count");
		}
		else if(c =='4')
		{
			count = 112;
			outint(count); outln(" = count");
		}
		else if(c =='5')
		{
			count = 140;
			outint(count); outln(" = count");
		}	
		else if(c =='6')
		{
			count = 168;
			outint(count); outln(" = count");
		}
		else if(c =='7')
		{
			count = 196;
			outint(count); outln(" = count");
		}
		else if(c =='8')
		{
			count = 224;
			outint(count); outln(" = count");
		}
		else if(c =='9')
		{
			count = 255;
			outint(count); outln(" = count");
		}
		else if(c == 'p')
		{
			outint(count); outln(" = count");
		}
		else if(c =='d')
		{
			if(db_correct == 0)
			{
				db_correct = 1;
				outln("Deadband Correction ON");
			}
			else
			{
				db_correct = 0;
				outln("Deadband Correction OFF");
			}
		}
		else if(c =='s')
		{
			count = 0;
			moving = 0;
			outint(count); outln(" = count, MOTOR STOPPED");
		}
		else if(c =='h')
		{
			outln("   + : Increment Value");
			outln("   - : Decrement Value");
			outln("   d : Enable or Disable (default) Deadband Comp.");
			outln("   r : Makes the Process Idle");
			outln("   a : Prints the Array Values to the Screen");
			outln(" 0-9 : Sets the Cd Value to a Value Between 0 and 255 in Equal Divisions");
			outln("   s : Stop the Motor");
			outln("   q : Quit");
		}
		else if (c == 'r') //breaks the 1 sec loop and sets j and count to 0
		{
			outint(AD_read()); outln(" = AD value\n");
			outint(count);
			//count = 0;
			//j = 0;
		}
		else if (c == 'a') //Dumps the entire array onto screen
		{
			int k;
			for (k=0; k<100; k++)
				outint (table[k]);
		}
		else if (c == 'q')
		{
			count = 0;
			moving = 0;
			outint(count); outln(" = count, QUITTING!!");
			break;
		}
	}
	sio_cleanup();

	return 1;
}