stm32 ad双通道dma模式说明

//通过脚PA1,PA2采集AD。每路AD采集10次。

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#include"ad_driver.h"

//全局变量

//AD采样存放空间

__IO uint16_tADCConvertedValue[20];

//函数

//初始化AD

void init_ad(void)

{

ADC_InitTypeDef ADC_InitStructure;

DMA_InitTypeDef DMA_InitStructure;

GPIO_InitTypeDef GPIO_InitStructure;

//---------------------充电AD初始化--------------------

//启动DMA时钟

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);

//启动ADC1时钟

RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);

//采样脚设置

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1 | GPIO_Pin_2;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;

GPIO_Init(GPIOA, &GPIO_InitStructure);

//DMA1通道1配置

DMA_DeInit(DMA1_Channel1);

//外设地址

DMA_InitStructure.DMA_PeripheralBaseAddr = ADC1_DR_ADDRESS;

//内存地址

DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)ADCConvertedValue;

//dma传输方向单向

DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;

//设置DMA在传输时缓冲区的长度

DMA_InitStructure.DMA_BufferSize = 20;

//设置DMA的外设递增模式，一个外设

DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;

//设置DMA的内存递增模式

DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;

//外设数据字长

DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;

//内存数据字长

DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;

//设置DMA的传输模式：连续不断的循环模式

DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;

//设置DMA的优先级别

DMA_InitStructure.DMA_Priority = DMA_Priority_High;

//设置DMA的2个memory中的变量互相访问

DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;

DMA_Init(DMA1_Channel1, &DMA_InitStructure);

//使能通道1

DMA_Cmd(DMA1_Channel1, ENABLE);

//ADC1配置

//独立工作模式

ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;

//扫描方式

ADC_InitStructure.ADC_ScanConvMode = ENABLE;

//连续转换

ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;

//外部触发禁止

ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;

//数据右对齐

ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;

//用于转换的通道数

ADC_InitStructure.ADC_NbrOfChannel = 2;

ADC_Init(ADC1, &ADC_InitStructure);

//规则模式通道配置

ADC_RegularChannelConfig(ADC1, ADC_Channel_1 , 1, ADC_SampleTime_239Cycles5);

ADC_RegularChannelConfig(ADC1, ADC_Channel_2 , 2, ADC_SampleTime_239Cycles5);

//使能ADC1的DMA

ADC_DMACmd(ADC1, ENABLE);

//使能ADC1

ADC_Cmd(ADC1, ENABLE);

//使能ADC1复位校准寄存器

ADC_ResetCalibration(ADC1);

//检查校准寄存器是否复位完毕

while(ADC_GetResetCalibrationStatus(ADC1));

//开始校准

ADC_StartCalibration(ADC1);

//检测是否校准完毕

while(ADC_GetCalibrationStatus(ADC1));

//开启ADC1的软件转换

ADC_SoftwareStartConvCmd(ADC1, ENABLE);

}

//获得充电电压

float voltage_charge(void)

{

uint8_t i = 0;

uint16_t sum = 0;

float v = 0;

//取得10次充电电压平均值

for (i = 0;i < 10;i++)

{

sum += ADCConvertedValue[i * 2];

}

sum /= 10;

//变换成电压值

v = 0.002991 * sum;

return v;

}

//获得放电电压

float voltage_discharge(void)

{

uint8_t i = 0;

uint16_t sum = 0;

float v = 0;

//取得10次充电电压平均值

for (i = 0;i < 10;i++)

{

sum += ADCConvertedValue[i * 2 + 1];

}

sum /= 10;

//变换成电压值

v = 0.002991 * sum;

return v;

}