GD32F103 AD采样问题

只看该作者 · 2021-7-21 10:08

GD32F103 IO口设置成模拟输入时，发现IO口有高电平输出，导致ad采样电压偏高，不知道怎么解决？

只看该作者 · 2021-7-21 10:30

具体代码如下：
void dma_config(void)
{
/* ADC_DMA_channel configuration */
dma_parameter_struct dma_data_parameter;

/* ADC DMA_channel configuration */
dma_deinit(DMA0, DMA_CH0);

/* initialize DMA single data mode */
dma_data_parameter.periph_addr  = (uint32_t)(&ADC_RDATA(ADC0));
dma_data_parameter.periph_inc = DMA_PERIPH_INCREASE_DISABLE;
dma_data_parameter.memory_addr  = (uint32_t)(&adc_value);
dma_data_parameter.memory_inc = DMA_MEMORY_INCREASE_ENABLE;
dma_data_parameter.periph_width = DMA_PERIPHERAL_WIDTH_16BIT;
dma_data_parameter.memory_width = DMA_MEMORY_WIDTH_16BIT;
dma_data_parameter.direction = DMA_PERIPHERAL_TO_MEMORY;
dma_data_parameter.number    = 5U;
dma_data_parameter.priority    = DMA_PRIORITY_HIGH;
dma_init(DMA0, DMA_CH0, &dma_data_parameter);
dma_circulation_enable(DMA0, DMA_CH0);

/* enable DMA channel */
dma_channel_enable(DMA0, DMA_CH0);
}
void adcinit(void)
{

rcu_periph_clock_enable(RCU_GPIOA);
gpio_init(GPIOA,GPIO_MODE_AIN,GPIO_OSPEED_2MHZ, GPIO_PIN_6|GPIO_PIN_7);
rcu_periph_clock_enable(RCU_GPIOB);
gpio_init(GPIOB,GPIO_MODE_AIN,GPIO_OSPEED_50MHZ, GPIO_PIN_0);
rcu_periph_clock_enable(RCU_GPIOC);
gpio_init(GPIOC,GPIO_MODE_AIN,GPIO_OSPEED_50MHZ, GPIO_PIN_5);

   /* enable DMA0 clock */
rcu_periph_clock_enable(RCU_DMA0);
dma_config();
   rcu_periph_clock_enable(RCU_ADC0);
   /* config ADC clock */
rcu_apb2_clock_config(RCU_APB2_CKAHB_DIV4);
rcu_adc_clock_config(RCU_CKADC_CKAPB2_DIV8);
      /* reset ADC */
adc_deinit(ADC0);
/* ADC mode config */
adc_mode_config(ADC_MODE_FREE);
adc_tempsensor_vrefint_enable();
/* ADC contineous function enable */
adc_special_function_config(ADC0, ADC_CONTINUOUS_MODE, ENABLE);
/* ADC scan mode disable */
adc_special_function_config(ADC0, ADC_SCAN_MODE, ENABLE);
/* ADC data alignment config */
adc_data_alignment_config(ADC0, ADC_DATAALIGN_RIGHT);
/* ADC channel length config */
adc_channel_length_config(ADC0, ADC_REGULAR_CHANNEL, 5);

/* ADC regular channel config */
adc_regular_channel_config(ADC0, 0, ADC_CHANNEL_6, ADC_SAMPLETIME_239POINT5);
adc_regular_channel_config(ADC0, 1, ADC_CHANNEL_7, ADC_SAMPLETIME_239POINT5);
adc_regular_channel_config(ADC0, 2, ADC_CHANNEL_15, ADC_SAMPLETIME_239POINT5);
adc_regular_channel_config(ADC0, 3, ADC_CHANNEL_8, ADC_SAMPLETIME_239POINT5);
   adc_regular_channel_config(ADC0, 4, ADC_CHANNEL_17, ADC_SAMPLETIME_239POINT5);
/* ADC trigger config */
adc_external_trigger_source_config(ADC0, ADC_REGULAR_CHANNEL, ADC0_1_2_EXTTRIG_REGULAR_NONE);
adc_external_trigger_config(ADC0, ADC_REGULAR_CHANNEL, ENABLE);

/* enable ADC interface */
adc_enable(ADC0);
delay_1ms(1);
/* ADC calibration and reset calibration */
adc_calibration_enable(ADC0);

/* ADC DMA function enable */
adc_dma_mode_enable(ADC0);
/* ADC software trigger enable */
adc_software_trigger_enable(ADC0, ADC_REGULAR_CHANNEL);

}