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static bool isInit = false;
static float temp;
static float vref;

void tmp36Task(void *param);

void tmp36Init()
{
	if (isInit) return;

	/* Define ADC init structures */
	ADC_InitTypeDef       ADC_InitStructure;
	ADC_CommonInitTypeDef ADC_CommonInitStructure;
	GPIO_InitTypeDef GPIO_InitStructure;

	/* IMPORTANT: populates structures with reset values */
	ADC_StructInit(&ADC_InitStructure);
	ADC_CommonStructInit(&ADC_CommonInitStructure);

	/* enable ADC clock */
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);

	/* init GPIO */
	GPIO_StructInit(&GPIO_InitStructure);
	GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_6;
	GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_AN;
	GPIO_InitStructure.GPIO_Speed = GPIO_Low_Speed;
	GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_NOPULL;
	GPIO_Init(GPIOA, &GPIO_InitStructure);

	/* init ADCs in independent mode, div clock by two */
	ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;
	ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div2;
	ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_Disabled;
	ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles;
	ADC_CommonInit(&ADC_CommonInitStructure);

	/* init ADC1: 12bit, single-conversion */
	ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
	ADC_InitStructure.ADC_ScanConvMode = DISABLE;
	ADC_InitStructure.ADC_ContinuousConvMode = DISABLE;
	ADC_InitStructure.ADC_ExternalTrigConvEdge = 0;
	ADC_InitStructure.ADC_ExternalTrigConv = 0;
	ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
	ADC_InitStructure.ADC_NbrOfConversion = 1;
	ADC_Init(ADC1, &ADC_InitStructure);

	/* Enable VREF_INT & Temperature channel */
	ADC_TempSensorVrefintCmd(ENABLE);

	/* Enable ADC1 **************************************************************/
	ADC_Cmd(ADC1, ENABLE);

	xTaskCreate(tmp36Task, (const signed char * const)"tmp36",
			configMINIMAL_STACK_SIZE, NULL, 3, NULL);

	isInit = true;
}

bool tmp36Test(void)
{
	return isInit;
}

float adc_read(ADC_TypeDef* ADCx, uint8_t channel, uint8_t ADC_SampleTime) {
	/* Configure Channel */
	ADC_RegularChannelConfig(ADCx, channel, 1, ADC_SampleTime);

	/* check if conversion was started, if not start */
	ADC_SoftwareStartConv(ADCx);

	/* wait for end of conversion */
	while((ADC_GetFlagStatus(ADCx, ADC_FLAG_EOC) == RESET));

	return (float)ADC_GetConversionValue(ADCx);
}

void tmp36Task(void *param)
{
	float val;

	vTaskSetApplicationTaskTag(0, (void*)TASK_ADC_ID_NBR);
	vTaskDelay(1000);

	while(1)
	{
		val = adc_read(ADC1, ADC_Channel_7, ADC_SampleTime_480Cycles);
		vref = adc_read(ADC1, ADC_Channel_17, ADC_SampleTime_480Cycles);

		//I am attemping to get the voltage reading and not actually converting it
		//to the temperature value yet.
		temp = val / (vref / 1.2); //ADC internal vref is 1.2v
	}
}

LOG_GROUP_START(TMP36)
LOG_ADD(LOG_FLOAT, tmp36, &temp)
LOG_GROUP_STOP(TMP36)