STM32 ADC多通道转换
描述:用ADC连续采集11路模拟信号,并由DMA传输到内存。ADC配置为扫描并且连续转换模式,ADC的时钟配置为12MHZ。在每次转换结束后,由DMA循环将转换的数据传输到内存中。ADC可以连续采集N次求平均值。最后通过串口传输出最后转换的结果。
程序如下:
- #i nclude "stm32f10x.h" //这个头文件包括STM32F10x所有外围寄存器、位、内存映射的定义
- #i nclude "eval.h" //头文件(包括串口、按键、LED的函数声明)
- #i nclude "SysTickDelay.h"
- #i nclude "UART_INTERFACE.h"
- #i nclude <stdio.h>
- #define N 50 //每通道采50次
- #define M 12 //为12个通道
- vu16 AD_Value[N][M]; //用来存放ADC转换结果,也是DMA的目标地址
- vu16 After_filter[M]; //用来存放求平均值之后的结果
- int i;
- void GPIO_Configuration(void)
- {
- GPIO_InitTypeDef GPIO_InitStructure;
- GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
- GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //因为USART1管脚是以复用的形式接到GPIO口上的,所以使用复用推挽式输出
- GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
- GPIO_Init(GPIOA, &GPIO_InitStructure);
- GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
- GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
- GPIO_Init(GPIOA, &GPIO_InitStructure);
- //PA0/1/2 作为模拟通道输入引脚
- GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0| GPIO_Pin_1|GPIO_Pin_2|GPIO_Pin_3;
- GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN; //模拟输入引脚
- GPIO_Init(GPIOA, &GPIO_InitStructure);
- //PB0/1 作为模拟通道输入引脚
- GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1;
- GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN; //模拟输入引脚
- GPIO_Init(GPIOB, &GPIO_InitStructure);
- //PC0/1/2/3/4/5 作为模拟通道输入引脚
- GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1|GPIO_Pin_2|GPIO_Pin_3|GPIO_Pin_4|GPIO_Pin_5;
- GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN; //模拟输入引脚
- GPIO_Init(GPIOC, &GPIO_InitStructure);
- }
- }
- void RCC_Configuration(void)
- {
- ErrorStatus HSEStartUpStatus;
- RCC_DeInit(); //RCC 系统复位
- RCC_HSEConfig(RCC_HSE_ON); //开启HSE
- HSEStartUpStatus = RCC_WaitForHSEStartUp(); //等待HSE准备好
- if(HSEStartUpStatus == SUCCESS)
- {
- FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable); //Enable Prefetch Buffer
- FLASH_SetLatency(FLASH_Latency_2); //Set 2 Latency cycles
- RCC_HCLKConfig(RCC_SYSCLK_Div1); //AHB clock = SYSCLK
- RCC_PCLK2Config(RCC_HCLK_Div1); //APB2 clock = HCLK
- RCC_PCLK1Config(RCC_HCLK_Div2); //APB1 clock = HCLK/2
- RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_6); //PLLCLK = 12MHz * 6 = 72 MHz
- RCC_PLLCmd(ENABLE); //Enable PLL
- while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET); //Wait till PLL is ready
- RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK); //Select PLL as system clock source
- while(RCC_GetSYSCLKSource() != 0x08); //Wait till PLL is used as system clock source
- RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_GPIOB
- | RCC_APB2Periph_GPIOC |RCC_APB2Periph_ADC1 | RCC_APB2Periph_AFIO |RCC_APB2Periph_USART1, ENABLE ); //使能ADC1通道时钟,各个管脚时钟
- RCC_ADCCLKConfig(RCC_PCLK2_Div6); //72M/6=12,ADC最大时间不能超过14M
- RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE); //使能DMA传输
- }
- }
- void ADC1_Configuration(void)
- {
- ADC_InitTypeDef ADC_InitStructure;
- ADC_DeInit(ADC1); //将外设 ADC1 的全部寄存器重设为缺省值
- ADC_InitStructure.ADC_Mode = ADC_Mode_Independent; //ADC工作模式:ADC1和ADC2工作在独立模式
- ADC_InitStructure.ADC_ScanConvMode =ENABLE; //模数转换工作在扫描模式
- ADC_InitStructure.ADC_ContinuousConvMode = ENABLE; //模数转换工作在连续转换模式
- ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None; //外部触发转换关闭
- ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; //ADC数据右对齐
- ADC_InitStructure.ADC_NbrOfChannel = M; //顺序进行规则转换的ADC通道的数目
- ADC_Init(ADC1, &ADC_InitStructure); //根据ADC_InitStruct中指定的参数初始化外设ADCx的寄存器
- //设置指定ADC的规则组通道,设置它们的转化顺序和采样时间
- //ADC1,ADC通道x,规则采样顺序值为y,采样时间为239.5周期
- ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 2, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_2, 3, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_3, 4, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_8, 5, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_9, 6, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_10, 7, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_11, 8, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_12, 9, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_13, 10, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_14, 11, ADC_SampleTime_239Cycles5 );
- ADC_RegularChannelConfig(ADC1, ADC_Channel_15, 12, ADC_SampleTime_239Cycles5 );
- // 开启ADC的DMA支持(要实现DMA功能,还需独立配置DMA通道等参数)
- ADC_DMACmd(ADC1, ENABLE);
- ADC_Cmd(ADC1, ENABLE); //使能指定的ADC1
- ADC_ResetCalibration(ADC1); //复位指定的ADC1的校准寄存器
- while(ADC_GetResetCalibrationStatus(ADC1)); //获取ADC1复位校准寄存器的状态,设置状态则等待
- ADC_StartCalibration(ADC1); //开始指定ADC1的校准状态
- while(ADC_GetCalibrationStatus(ADC1)); //获取指定ADC1的校准程序,设置状态则等待
- }
- void DMA_Configuration(void)
- {
- DMA_InitTypeDef DMA_InitStructure;
- DMA_DeInit(DMA1_Channel1); //将DMA的通道1寄存器重设为缺省值
- DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)&ADC1->DR; //DMA外设ADC基地址
- DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&AD_Value; //DMA内存基地址
- DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; //内存作为数据传输的目的地
- DMA_InitStructure.DMA_BufferSize = N*M; //DMA通道的DMA缓存的大小
- DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //外设地址寄存器不变
- DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //内存地址寄存器递增
- DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord; //数据宽度为16位
- DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord; //数据宽度为16位
- DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; //工作在循环缓存模式
- DMA_InitStructure.DMA_Priority = DMA_Priority_High; //DMA通道 x拥有高优先级
- DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; //DMA通道x没有设置为内存到内存传输
- DMA_Init(DMA1_Channel1, &DMA_InitStructure); //根据DMA_InitStruct中指定的参数初始化DMA的通道
- }
- //配置所有外设
- void Init_All_Periph(void)
- {
- RCC_Configuration();
- GPIO_Configuration();
- ADC1_Configuration();
- DMA_Configuration();
- //USART1_Configuration();
- USART_Configuration(9600);
- }
- u16 GetVolt(u16 advalue)
- {
- return (u16)(advalue * 330 / 4096); //求的结果扩大了100倍,方便下面求出小数
- }
- void filter(void)
- {
- int sum = 0;
- u8 count;
- for(i=0;i<12;i++)
- {
- for ( count=0;count<N;count++)
- {
- sum += AD_Value[count][i];
- }
- After_filter[i]=sum/N;
- sum=0;
- }
- }
- int main(void)
- {
- u16 value[M];
- init_All_Periph();
- SysTick_Initaize();
- ADC_SoftwareStartConvCmd(ADC1, ENABLE);
- DMA_Cmd(DMA1_Channel1, ENABLE); //启动DMA通道
- while(1)
- {
- while(USART_GetFlagStatus(USART1,USART_FLAG_TXE)==RESET);//等待传输完成否则第一位数据容易丢失
- filter();
- for(i=0;i<12;i++)
- {
- value[i]= GetVolt(After_filter[i]);
- printf("value[%d]:\t%d.%dv\n",i,value[i]/100,value[i]0) ;
- delay_ms(100);
- }
- }
- }
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