#include <msp430.h> 
#include <stdint.h>

/*
 * main.c
 */
#define DRIVE_CNT						2000
#define PULSE_OUTPUT_PIN				BIT2
//
#define STATE_TIMER0					0x0010
#define STATE_NULL						0x0000
//.....
uint16_t state;
int16_t drive_out= 0;

//returns error code
uint16_t measure_adc10( int16_t* p_val_store );
#define ADC_CTL1_PARAMS		0
#define ERR_ADC_TIMOUT		1
#define SAFTY_MAXADC_COUNT	32

#define ETEMP_SENSE			BIT3
#define ETEMP_INCH			INCH_3
#define POT_A_SENSE			BIT4
#define POT_A_INCH			INCH_4
#define POT_B_SENSE			BIT5
#define POT_B_INCH			INCH_5

#define SAMPLES				4

uint16_t error;
int16_t temp_sense;
int16_t pot_a_sense;
int16_t pot_b_sense;
// .........

int main(void) {
    WDTCTL = WDTPW | WDTHOLD;	// Stop watchdog timer
	
	P1DIR|= PULSE_OUTPUT_PIN;
	P2OUT|= PULSE_OUTPUT_PIN;

	//counter for PWM output
	TACCR0= DRIVE_CNT; // + limit_set;
    P1SEL|= PULSE_OUTPUT_PIN;
    //SMCLK, Up Mode, Clear
    TACTL= TASSEL_2 | MC_1 | TACLR | ID_0;
    //Interrupt
    TACCTL0= CCIE;
    //control_1 set/reset
    TACCTL1= OUTMOD_3;

	//the adc...
	///Vref ~ Vss to ref; ref on;  SHT * 16 clock
    ADC10CTL0= SREF_1 | REF2_5V | REFON | ADC10SHT_1;

    _enable_interrupt( );

    for( ; ; )
    {
    	if( ! state )
    		continue;

    	//for now, state will only be STATE_TIMER0;
    	//measure temperature of engine
		ADC10AE0= POT_A_SENSE;
	    ADC10CTL1= POT_A_INCH | ADC_CTL1_PARAMS;
	    error= measure_adc10( &pot_a_sense );

	    ADC10AE0= POT_B_SENSE;
	    ADC10CTL1= POT_B_INCH | ADC_CTL1_PARAMS;
	    error+= measure_adc10( &pot_b_sense );

		ADC10AE0= ETEMP_SENSE;
		ADC10CTL1= ETEMP_INCH | ADC_CTL1_PARAMS;
		error+= measure_adc10( &temp_sense );
/*
 *
		temp_sense= 0;
		int16_t temp;
		uint8_t c= 0;
		for( ; c < SAMPLES; ++c )
		{
			error+= measure_adc10( &temp );
			temp_sense+= temp;
		}
		temp_sense/= SAMPLES;
*/
		//....
		pot_a_sense= 1024 - pot_a_sense;
		int16_t temp;
		if( pot_a_sense > temp_sense )
		{
			temp= ( pot_a_sense - temp_sense )
				* ( pot_b_sense / 30 );
			if( temp > DRIVE_CNT )
				temp= DRIVE_CNT;

			temp+=1;
			temp-=1;
			if( temp > 70 )
				drive_out= temp;
		}
		else
			drive_out= 0;

		state= STATE_NULL;
    }

//	return 0;
}

//returns error code
uint16_t measure_adc10( int16_t* p_val_store )
{
    ADC10CTL0|= ADC10ON | ENC | ADC10SC;
    uint16_t serror= 0;
    uint16_t temp_16= 0;
    for( ; ADC10CTL1 & ADC10BUSY; ++temp_16 )
    {
    	if( temp_16 > SAFTY_MAXADC_COUNT )
    	{
    	    ADC10CTL0&= ~( ENC | ADC10ON );
    	    serror= ERR_ADC_TIMOUT;
    	}
    }
    *p_val_store= ADC10MEM;
	ADC10CTL0&= ~( ENC | ADC10ON );
	return serror;
}
#define SAMPLES		1


#pragma vector= TIMER0_A0_VECTOR
__interrupt void timer0_interrupt( )
{
	TACCR1= drive_out;
	state|= STATE_TIMER0;
}