采用stm32f1开发板，使用ADC的定时器触发ADC转换的功能，然后使用DMA进行数据的搬运。采用TIM2定时器的触发间隔，实现ADC定时采样转换的功能，然后可以在程序的死循环中一直检测DMA转换完成标志，然后进行数据的读取，或者使能DMA转换完成中断，这样每次转换完成就会产生中断。
完整源码：
定时器触发ADC实验.7z
(221.91 KB, 售价: 1 工控币)
## 定时器2初始化函数
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_TimeBaseStructure.TIM_Period = arr; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值
TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割:TDTS = Tck_tim
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure); //根据指定的参数初始化TIMx的时间基数单位
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //选择定时器模式:TIM脉冲宽度调制模式1
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_Pulse = 1000;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low; //输出极性:TIM输出比较极性低
TIM_OC2Init(TIM2, & TIM_OCInitStructure); //初始化外设TIM2_CH2
TIM_Cmd(TIM2, ENABLE); //使能TIMx
TIM_CtrlPWMOutputs(TIM2, ENABLE);
## DMA配置
DMA_InitTypeDef DMA_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1,ENABLE); //使能ADC1通道时钟
DMA_DeInit(DMA1_Channel1);
DMA_InitStructure.DMA_PeripheralBaseAddr = ADC1_DR_Address; //ADC1地址
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)&ADC_ConvertedValue; //内存地址
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; //方向(从外设到内存)
DMA_InitStructure.DMA_BufferSize = 1; //传输内容的大小
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //外设地址固定
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Disable; //内存地址固定
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord ; //外设数据单位
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord ; //内存数据单位
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular ; //DMA模式：循环传输
DMA_InitStructure.DMA_Priority = DMA_Priority_High ; //优先级：高
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; //禁止内存到内存的传输
DMA_Init(DMA1_Channel1, &DMA_InitStructure); //配置DMA1
DMA_ITConfig(DMA1_Channel1,DMA_IT_TC, ENABLE); //使能传输完成中断
NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
DMA_Cmd(DMA1_Channel1,ENABLE);
## GPIO配置
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //使能GPIOA时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOA, &GPIO_InitStructure);
## ADC初始化
ADC_InitTypeDef ADC_InitStructure;
TIM2_Init(30000,7199); //72000000/7200=10000Hz，每3s采集一次
DMA1_Init();
ADC_GPIO_Configuration();
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE); //使能ADC1通道时钟
ADC_InitStructure.ADC_Mode = ADC_Mode_Independent; //独立ADC模式
ADC_InitStructure.ADC_ScanConvMode = DISABLE; //关闭扫描方式
ADC_InitStructure.ADC_ContinuousConvMode = DISABLE; //关闭连续转换模式
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_T2_CC2; //使用外部触发模式
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; //采集数据右对齐
ADC_InitStructure.ADC_NbrOfChannel = 1; //要转换的通道数目
ADC_Init(ADC1, &ADC_InitStructure);
## 注意事项
一定要在程序最前面定义ADC的采样数据和地址
volatile uint16_t ADC_ConvertedValue; //ADC采样的数据
#define ADC1_DR_Address ((u32)0x4001244C) //ADC1的地址
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