求助。用DMA方式进行双通道ADC转换，给其中一个通道的电压，这个通道AD转换完全正确，但是为什么另一个通道的电压值也会变化。原本以为AD采样太快，但是增加了采样时间还是会有这个问题。
[mw_shl_code=c,true]#include "adc_dma.h"
//#include "delay.h"
u16 __IO AD_Value[2];
void ADC1_Init(void)
{
ADC1_GPIO_Config();
ADC1_DMA_Config();
ADC1_Mode_Config();
}
static void ADC1_GPIO_Config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC,ENABLE);
GPIO_InitStructure.GPIO_Pin=GPIO_Pin_0|GPIO_Pin_1;
GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AIN;
GPIO_Init(GPIOC,&GPIO_InitStructure);
}
static void ADC1_DMA_Config(void)
{
DMA_InitTypeDef DMA_InitStructure;
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1,ENABLE);
DMA_DeInit(DMA1_Channel1);
DMA_InitStructure.DMA_PeripheralBaseAddr=(u32)&ADC1->DR;
DMA_InitStructure.DMA_MemoryBaseAddr=(u32)&AD_Value;
DMA_InitStructure.DMA_DIR=DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize=2;
DMA_InitStructure.DMA_PeripheralInc=DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc=DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize=DMA_PeripheralDataSize_HalfWord;
DMA_InitStructure.DMA_MemoryDataSize=DMA_MemoryDataSize_HalfWord;
DMA_InitStructure.DMA_Mode=DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority=DMA_Priority_Medium;
DMA_InitStructure.DMA_M2M=DMA_M2M_Disable;
DMA_Init(DMA1_Channel1,&DMA_InitStructure);
DMA_Cmd(DMA1_Channel1, ENABLE);
}
static void ADC1_Mode_Config(void)
{
ADC_InitTypeDef ADC_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1,ENABLE);
RCC_ADCCLKConfig(RCC_PCLK2_Div8);
ADC_DeInit(ADC1);
ADC_InitStructure.ADC_Mode=ADC_Mode_Independent;
ADC_InitStructure.ADC_ContinuousConvMode=ENABLE;
ADC_InitStructure.ADC_ScanConvMode=ENABLE;
ADC_InitStructure.ADC_ExternalTrigConv=ADC_ExternalTrigConv_None;
ADC_InitStructure.ADC_DataAlign=ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfChannel=2;
ADC_Init(ADC1,&ADC_InitStructure);
ADC_RegularChannelConfig(ADC1,ADC_Channel_10,1,ADC_SampleTime_239Cycles5);
ADC_RegularChannelConfig(ADC1,ADC_Channel_11,2,ADC_SampleTime_239Cycles5);
ADC_Cmd(ADC1,ENABLE);
ADC_DMACmd(ADC1,ENABLE);
ADC_ResetCalibration(ADC1);
while(ADC_GetResetCalibrationStatus(ADC1));
ADC_StartCalibration(ADC1);
while(ADC_GetCalibrationStatus(ADC1));
ADC_SoftwareStartConvCmd(ADC1, ENABLE);
}
u16 get_ChannelVale(u8 ADC_Channel)
{
u16 ret = 0;
switch(ADC_Channel)
{
case ADC_Channel_10:
ret = AD_Value[0];
break;
case ADC_Channel_11:
ret = AD_Value[1];
break;
}
return ret;
}[/mw_shl_code]
[mw_shl_code=c,true]#include "led.h"
#include "delay.h"
#include "sys.h"
#include "lcd.h"
#include "usart.h"
#include "adc_dma.h"
extern __IO u16 AD_Value[2];
int main(void)
{
u16 adcx;
float temp;
delay_init(); //???±??????????
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//?è????????????·?×é??×é2??2??????????????2???ì????????
uart_init(115200); //?®??????????115200
LED_Init(); //LED??????????
LCD_Init();
ADC1_Init(); //ADC??????
POINT_COLOR=RED;//?è??×??????ì??
LCD_ShowString(60,50,200,16,16,"WarShip STM32 ^_^");
LCD_ShowString(60,70,200,16,16,"ADC TEST");
LCD_ShowString(60,90,200,16,16,"ATOM@ALIENTEK");
LCD_ShowString(60,110,200,16,16,"2015/10/30");
//?????á??????
POINT_COLOR=BLUE;//?è??×?????????
LCD_ShowString(60,130,200,16,16,"ADC_CH0_VAL:");
LCD_ShowString(60,150,200,16,16,"ADC_CH0_VOL:0.000V");
POINT_COLOR=GREEN;//?è??×?????????
LCD_ShowString(60,170,200,16,16,"ADC_CH1_VAL:");
LCD_ShowString(60,190,200,16,16,"ADC_CH1_VOL:0.000V");
while(1)
{
POINT_COLOR=BLUE;//?è??×?????????
adcx=get_ChannelVale( ADC_Channel_10);
LCD_ShowxNum(156,130,adcx,4,16,0);//????ADC????
temp=(float)adcx*(3.3/4096);
adcx=temp;
LCD_ShowxNum(156,150,adcx,1,16,0);//??????????
temp-=adcx;
temp*=1000;
LCD_ShowxNum(172,150,temp,3,16,0X80);
POINT_COLOR=GREEN;//?è??×?????????
adcx=get_ChannelVale( ADC_Channel_11);
LCD_ShowxNum(156,170,adcx,4,16,0);//????ADC????
temp=(float)adcx*(3.3/4096);
adcx=temp;
LCD_ShowxNum(156,190,adcx,1,16,0);//??????????
temp-=adcx;
temp*=1000;
LCD_ShowxNum(172,190,temp,3,16,0X80);
LED2_REV;
delay_ms(250);
}
}[/mw_shl_code]
/2 
|手机版|OpenEdv-开源电子网
( 粤ICP备12000418号-1 )
发表于 2015-11-5 20:38:18
