#define iHN			 			9
#define iHZ						8
#define iVL						10
#define LOW_U_THR				100

static bool sequenceComplete, thresholdCrossed;
uint32_t HZ, HN, VL;

Chip_Clock_EnablePeriphClock(SYSCTL_CLOCK_SWM);
Chip_SWM_EnableFixedPin(SWM_FIXED_ADC8);
Chip_SWM_EnableFixedPin(SWM_FIXED_ADC9);
Chip_SWM_EnableFixedPin(SWM_FIXED_ADC10);
Chip_Clock_DisablePeriphClock(SYSCTL_CLOCK_SWM);

/*disable adc pullups on pins 13,17,18*/
Chip_Clock_EnablePeriphClock(SYSCTL_CLOCK_IOCON);
LPC_IOCON->PIO0[IOCON_PIO17] = 0;
LPC_IOCON->PIO0[IOCON_PIO18] = 0;
LPC_IOCON->PIO0[IOCON_PIO13] = 0;

static void ADC_Init(void){
	Chip_ADC_Init(LPC_ADC, 0);
	Chip_ADC_StartCalibration(LPC_ADC);
	while (!(Chip_ADC_IsCalibrationDone(LPC_ADC))) {}
	Chip_ADC_SetClockRate(LPC_ADC, 1000);//ADC_MAX_SAMPLE_RATE

	Chip_ADC_SetupSequencer(LPC_ADC, ADC_SEQA_IDX,
			(ADC_SEQ_CTRL_CHANSEL(iHZ) |
			ADC_SEQ_CTRL_CHANSEL(iHN) |
			ADC_SEQ_CTRL_CHANSEL(iVL) |
			ADC_SEQ_CTRL_MODE_EOS));
	/* Setup threshold 0 low and high values to about 25% and 75% of max */
	Chip_ADC_SetThrLowValue(LPC_ADC, 0, ((1 * 0xFFF) / 4));
	Chip_ADC_SetThrHighValue(LPC_ADC, 0, ((4 * 0xFFF) / 4));

	Chip_ADC_ClearFlags(LPC_ADC, Chip_ADC_GetFlags(LPC_ADC));/* Clear all pending interrupts */
	Chip_ADC_EnableInt(LPC_ADC, (ADC_INTEN_SEQA_ENABLE | ADC_INTEN_OVRRUN_ENABLE));/* Enable ADC overrun and sequence A completion interrupts */

	/* Enable ADC NVIC interrupt */
	NVIC_EnableIRQ(ADC_SEQA_IRQn);

	/* Enable sequencer */
	Chip_ADC_EnableSequencer(LPC_ADC, ADC_SEQA_IDX);
}

void ADC_SEQA_IRQHandler(void)
{
	uint32_t pending;

	/* Get pending interrupts */
	pending = Chip_ADC_GetFlags(LPC_ADC);

	/* Sequence A completion interrupt */
	if (pending & ADC_FLAGS_SEQA_INT_MASK) {
		sequenceComplete = true;
	}

	/* Threshold crossing interrupt on ADC input channel */
	if (pending & ADC_FLAGS_THCMP_MASK(iHN) & ADC_FLAGS_THCMP_MASK(iHZ) & ADC_FLAGS_THCMP_MASK(iVL)) {
		thresholdCrossed = true;
	}

	/* Clear any pending interrupts */
	Chip_ADC_ClearFlags(LPC_ADC, pending);
}

void SysTick_Handler(void)
{
	static uint32_t count;

	/* Every 1/2 second */
	if (count++ == 100 / 2) {
		count = 0;

		/* Manual start for ADC conversion sequence A */
		Chip_ADC_StartSequencer(LPC_ADC, ADC_SEQA_IDX);
	}
}

int main(void) {
    SystemCoreClockUpdate();
    ADC_Init();
    SysTick_Config(SystemCoreClock / 100);

    if (sequenceComplete) {
    	sequenceComplete = false;

		HZ = ADC_DR_RESULT(LPC_ADC->DR[iHZ]);
    	HN = ADC_DR_RESULT(LPC_ADC->DR[iHN]);
    	VL = ADC_DR_RESULT(LPC_ADC->DR[iVL]);
    }
}