GD32F407 ADC+DMA

#define VDDA_APPLI                     ((uint32_t) 3300)    /* Value of analog voltage supply Vdda (unit: mV) */
#define RANGE_12BITS                   ((uint8_t) 12)    //移位/* Max digital value with a full range of 12 bits */

#define COMPUTATION_DIGITAL_12BITS_TO_VOLTAGE(ADC_DATA)	 ( ((ADC_DATA) * VDDA_APPLI ) >> RANGE_12BITS)

uint16_t g_adc_dma_data[DRI_ADC_TIMES * DRI_ADC_NUMBER] = {0};

int dri_dma1_channel0_init(void)
{
	dma_single_data_parameter_struct dma_init;
	
	rcu_periph_clock_enable(RCU_DMA1);
	
	dma_deinit(DMA1, DMA_CH0);
	dma_init.periph_addr = (uint32_t)(&ADC_RDATA(ADC0));
	dma_init.periph_inc = DMA_PERIPH_INCREASE_DISABLE;
	dma_init.memory0_addr = (uint32_t)g_adc_dma_data;
	dma_init.memory_inc = DMA_MEMORY_INCREASE_ENABLE;
	dma_init.periph_memory_width = DMA_PERIPH_WIDTH_16BIT;	
	dma_init.priority = DMA_PRIORITY_HIGH;
	dma_init.circular_mode = DMA_CIRCULAR_MODE_ENABLE;
	dma_init.direction = DMA_PERIPH_TO_MEMORY;
	dma_init.number = DRI_ADC_TIMES * DRI_ADC_NUMBER;
	
	dma_single_data_mode_init(DMA1, DMA_CH0, &dma_init);
	
	/* enable DMA circulation mode */
    dma_circulation_enable(DMA1, DMA_CH0);
	
	return 0;
}

int dri_adc0_init(void)
{
	/* enable ADC clock */
	rcu_periph_clock_enable(RCU_ADC0);
	/* config ADC clock */
	adc_clock_config(ADC_ADCCK_PCLK2_DIV6);
	
	
	rcu_periph_clock_enable(RCU_GPIOA);
	/* config the GPIO as analog mode */
#if OPT_CHECK_EN > 0u
	gpio_mode_set(DRI_ADC_OPT_PORT, GPIO_MODE_ANALOG, GPIO_PUPD_NONE, DRI_ADC_OPT_PIN);
#endif	
#if RF_CHECK_EN > 0u
	gpio_mode_set(DRI_ADC_RF_PORT, GPIO_MODE_ANALOG, GPIO_PUPD_NONE, DRI_ADC_RF_PIN);
#endif
	
	/*reset all*/
	adc_deinit();
	/*!< ADC synchronization mode disabled.All the ADCs work independently */
	adc_sync_mode_config(ADC_SYNC_MODE_INDEPENDENT);
	/*连续模式*/
	adc_special_function_config(ADC0, ADC_CONTINUOUS_MODE, ENABLE);
	/*扫描模式*/
	adc_special_function_config(ADC0, ADC_SCAN_MODE, ENABLE); 
	/* ADC channel length(num) config */
	adc_channel_length_config(ADC0,ADC_ROUTINE_CHANNEL, 2);
	/* ADC data alignment config */
	adc_data_alignment_config(ADC0, ADC_DATAALIGN_RIGHT);
	/* ADC resolusion 12B */
	adc_resolution_config(ADC0,ADC_RESOLUTION_12B);
	/*禁用外部触发，只能使用软件触发*/
	adc_external_trigger_source_config(ADC0, ADC_ROUTINE_CHANNEL, ADC_EXTTRIG_ROUTINE_T0_CH0);
	adc_external_trigger_config(ADC0, ADC_ROUTINE_CHANNEL, ENABLE);
	/* ADC routine channel config */
#if OPT_CHECK_EN > 0u
		adc_routine_channel_config(ADC0, 0 , DRI_ADC_CHENNEL_OPTICAL, ADC_SAMPLETIME_15);
#endif
#if RF_CHECK_EN > 0u
		adc_routine_channel_config(ADC0, 1 , DRI_ADC_CHENNEL_RF, ADC_SAMPLETIME_15);
#endif

	adc_end_of_conversion_config(ADC0, ADC_EOC_SET_CONVERSION);

	adc_dma_request_after_last_enable(ADC0);
	adc_dma_mode_enable(ADC0);
	
	/* enable ADC interface */
	adc_enable(ADC0);
	dri_timer_delay_us(1000);
	/* wait for ADC stability */
	/* ADC calibration and reset calibration */
	adc_calibration_enable(ADC0);
	
	return 0;
}

void dri_adc0_dma1_init(void)
{	
	dri_adc0_init();
	dri_dma1_channel0_init();
	
	/*使能DMA通道*/
	dma_channel_enable(DMA1, DMA_CH0); 
	/*软件触发*/
	adc_software_trigger_enable(ADC0, ADC_ROUTINE_CHANNEL);
}

static uint32_t dri_adc_sample_filter(uint32_t ulADCChannel, uint16_t *pusSample)
{	
	uint16_t i = 0;	
	uint16_t strtcnt = 0;
	uint32_t filterValue = 0;
	
#if RF_CHECK_EN && OPT_CHECK_EN
    if(ulADCChannel == DRI_ADC_CHENNEL_OPTICAL)
		strtcnt = 0;
	else 
		strtcnt = 1;
#else
    strtcnt = 0;
#endif	
	
	for(i = strtcnt; i < DRI_ADC_TIMES * DRI_ADC_NUMBER; i += DRI_ADC_NUMBER)
	{
	    filterValue += pusSample[i];
	}
	ADC_DEBUG("filterValue %d\r\n", filterValue);
	filterValue /= DRI_ADC_TIMES;

	return filterValue;
}

uint16_t dri_adc_convert(uint32_t ulADCChannel, uint8_t ucMode)
{	
	uint32_t ulSampleAvg = 0;
    uint16_t fVoltage    = 0;
	
	ulSampleAvg = dri_adc_sample_filter(ulADCChannel, g_adc_dma_data);
	switch(ucMode)
	{
		case DRI_ADC_OUTPUT_VOLTAGE:
            fVoltage = COMPUTATION_DIGITAL_12BITS_TO_VOLTAGE(ulSampleAvg);
            break;
        default:
            fVoltage = (uint16_t)ulSampleAvg;
            break;
	}

    return fVoltage;
}