APM32F407微控制器中的模数转换器（ADC）是一种12位逐次逼近型转换器，用于将模拟信号（如电压）转换为数字值，支持高精度数据采集。该模块具备以下核心特性：
主要特性
分辨率与精度：支持12位、10位、8位或6位可配置分辨率，最小量化误差低，可通过自校准提升精度。输入电压范围由VREF-至VREF+（典型值VREF+连接VDDA=3.3V）。
通道配置：
最多24个外部通道：每个 ADC 最多有 16 个外部通道、3个内部通道（温度传感器、内部参考电压VREFINT和备份电压）、以及VBAT电池监控通道。
通道分为规则组（最多16通道，用于常规转换）和注入组（最多4通道，支持高优先级中断式转换）。
转换模式：
支持单次转换、连续转换、扫描模式（自动顺序转换多个通道）和间断模式（分组触发）。
双重或三重ADC模式（ADC1与ADC2和ADC3可协同工作）。
数据处理：结果以左对齐或右对齐16位数据寄存器存储，支持DMA传输（减少CPU开销）和中断机制（用于转换结束或看门狗事件）。
其他功能：软件或外部触发启动转换，采样时间按通道可编程，模拟看门狗监控输入阈值超限。
采样速率：支持最高2.4 MSPS（每秒百万次采样）的单通道速度；通过交替模式，可提升至7.2 MSPS，满足高速数据应用需求。
APM32F407的有三个ADC,除了可以每个ADC单独工作外，还有双重ADC和三重ADC模式，可以实现更丰富的功能。接下来就测试下三重ADC的同时规则模式，三个ADC同时采各种的通道，实现多通道ADC采样有更快的速度。
首先是ADC和DMA的初始化
void ADC_Init(void)
{
GPIO_Config_T gpioConfig;
ADC_Config_T adcConfig;
ADC_CommonConfig_T adcCommonConfig;
/* RCM Enable*/
RCM_EnableAHB1PeriphClock(RCM_AHB1_PERIPH_GPIOA|RCM_AHB1_PERIPH_GPIOB|RCM_AHB1_PERIPH_GPIOC);
/* GPIO Configuration */
GPIO_ConfigStructInit(&gpioConfig);
gpioConfig.pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_4|GPIO_PIN_5|GPIO_PIN_6;
gpioConfig.mode = GPIO_MODE_AN;
gpioConfig.pupd = GPIO_PUPD_NOPULL;
GPIO_Config(GPIOA, &gpioConfig);
GPIO_ConfigStructInit(&gpioConfig);
gpioConfig.pin = GPIO_PIN_0|GPIO_PIN_1;
gpioConfig.mode = GPIO_MODE_AN;
gpioConfig.pupd = GPIO_PUPD_NOPULL;
GPIO_Config(GPIOB, &gpioConfig);
GPIO_ConfigStructInit(&gpioConfig);
gpioConfig.pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3;
gpioConfig.mode = GPIO_MODE_AN;
gpioConfig.pupd = GPIO_PUPD_NOPULL;
GPIO_Config(GPIOC, &gpioConfig);
RCM_EnableAPB2PeriphClock(RCM_APB2_PERIPH_ADC1);
RCM_EnableAPB2PeriphClock(RCM_APB2_PERIPH_ADC2);
RCM_EnableAPB2PeriphClock(RCM_APB2_PERIPH_ADC3);
ADC_Reset();
/* ADC Common Configuration */
adcCommonConfig.mode = ADC_MODE_TRIPLE_REGSIMULT;
adcCommonConfig.prescaler = ADC_PRESCALER_DIV6;
adcCommonConfig.accessMode = ADC_ACCESS_MODE_1;
adcCommonConfig.twoSampling = ADC_TWO_SAMPLING_10CYCLES;
ADC_CommonConfig(&adcCommonConfig);
/* ADC Configuration */
ADC_ConfigStructInit(&adcConfig);
/* Set resolution*/
adcConfig.resolution = ADC_RESOLUTION_12BIT;
/* Set dataAlign*/
adcConfig.dataAlign = ADC_DATA_ALIGN_RIGHT;
/* Set scanDir*/
adcConfig.scanConvMode = ENABLE;
/* Set convMode continous*/
adcConfig.continuousConvMode = ENABLE;
/* Set extTrigEdge*/
adcConfig.extTrigEdge = ADC_EXT_TRIG_EDGE_NONE;
/* Set nbrOfConversion*/
adcConfig.nbrOfChannel = 4;
ADC_Config(ADC1, &adcConfig);
ADC_ConfigRegularChannel(ADC1, ADC_CHANNEL_0, 1, ADC_SAMPLETIME_3CYCLES);
ADC_ConfigRegularChannel(ADC1, ADC_CHANNEL_1, 2, ADC_SAMPLETIME_3CYCLES);
ADC_ConfigRegularChannel(ADC1, ADC_CHANNEL_2, 3, ADC_SAMPLETIME_3CYCLES);
ADC_ConfigRegularChannel(ADC1, ADC_CHANNEL_4, 4, ADC_SAMPLETIME_3CYCLES);
ADC_Config(ADC2, &adcConfig);
ADC_ConfigRegularChannel(ADC2, ADC_CHANNEL_5, 1, ADC_SAMPLETIME_3CYCLES);
ADC_ConfigRegularChannel(ADC2, ADC_CHANNEL_6, 2, ADC_SAMPLETIME_3CYCLES);
ADC_ConfigRegularChannel(ADC2, ADC_CHANNEL_8, 3, ADC_SAMPLETIME_3CYCLES);
ADC_ConfigRegularChannel(ADC2, ADC_CHANNEL_9, 4, ADC_SAMPLETIME_3CYCLES);
ADC_Config(ADC3, &adcConfig);
ADC_ConfigRegularChannel(ADC3, ADC_CHANNEL_10, 1, ADC_SAMPLETIME_3CYCLES);
ADC_ConfigRegularChannel(ADC3, ADC_CHANNEL_11, 2, ADC_SAMPLETIME_3CYCLES);
ADC_ConfigRegularChannel(ADC3, ADC_CHANNEL_12, 3, ADC_SAMPLETIME_3CYCLES);
ADC_ConfigRegularChannel(ADC3, ADC_CHANNEL_13, 4, ADC_SAMPLETIME_3CYCLES);
ADC_EnableMultiModeDMARequest();
/* Enable ADC*/
ADC_Enable(ADC1);
ADC_Enable(ADC2);
ADC_Enable(ADC3);
ADC_SoftwareStartConv(ADC1);
}主要的配置点:配置为3ADC同步规则模式
adcCommonConfig.mode = ADC_MODE_TRIPLE_REGSIMULT;
使能连续扫描模式，不使能触发
/* Set scanDir*/ adcConfig.scanConvMode = ENABLE; /* Set convMode continous*/ adcConfig.continuousConvMode = ENABLE; /* Set extTrigEdge*/ adcConfig.extTrigEdge = ADC_EXT_TRIG_EDGE_NONE;
配置各ADC的通道顺序
ADC_Config(ADC1, &adcConfig); ADC_ConfigRegularChannel(ADC1, ADC_CHANNEL_0, 1, ADC_SAMPLETIME_3CYCLES); ADC_ConfigRegularChannel(ADC1, ADC_CHANNEL_1, 2, ADC_SAMPLETIME_3CYCLES); ADC_ConfigRegularChannel(ADC1, ADC_CHANNEL_2, 3, ADC_SAMPLETIME_3CYCLES); ADC_ConfigRegularChannel(ADC1, ADC_CHANNEL_4, 4, ADC_SAMPLETIME_3CYCLES); ADC_Config(ADC2, &adcConfig); ADC_ConfigRegularChannel(ADC2, ADC_CHANNEL_5, 1, ADC_SAMPLETIME_3CYCLES); ADC_ConfigRegularChannel(ADC2, ADC_CHANNEL_6, 2, ADC_SAMPLETIME_3CYCLES); ADC_ConfigRegularChannel(ADC2, ADC_CHANNEL_8, 3, ADC_SAMPLETIME_3CYCLES); ADC_ConfigRegularChannel(ADC2, ADC_CHANNEL_9, 4, ADC_SAMPLETIME_3CYCLES); ADC_Config(ADC3, &adcConfig); ADC_ConfigRegularChannel(ADC3, ADC_CHANNEL_10, 1, ADC_SAMPLETIME_3CYCLES); ADC_ConfigRegularChannel(ADC3, ADC_CHANNEL_11, 2, ADC_SAMPLETIME_3CYCLES); ADC_ConfigRegularChannel(ADC3, ADC_CHANNEL_12, 3, ADC_SAMPLETIME_3CYCLES); ADC_ConfigRegularChannel(ADC3, ADC_CHANNEL_13, 4, ADC_SAMPLETIME_3CYCLES);
双重或三重 ADC 模式，ADC1 默认为主ADC，其他默认为从 ADC，只需要ADC1开始采样，其他ADC就也能工作。接下来是DMA的配置
查看用户手册，ADC1在DMA2的通道0 数据流0.根据这个进行配置
void DMA_Init(uint32_t* Buf)
{
/* DMA Configure */
DMA_Config_T dmaConfig;
/* Enable DMA clock */
RCM_EnableAHB1PeriphClock(RCM_AHB1_PERIPH_DMA2);
/* size of buffer*/
dmaConfig.bufferSize = 12;
/* set memory Data Size*/
dmaConfig.memoryDataSize = DMA_MEMORY_DATA_SIZE_HALFWORD;
/* Set peripheral Data Size*/
dmaConfig.peripheralDataSize = DMA_PERIPHERAL_DATA_SIZE_HALFWORD;
/* Enable Memory Address increase*/
dmaConfig.memoryInc = DMA_MEMORY_INC_ENABLE;
/* Disable Peripheral Address increase*/
dmaConfig.peripheralInc = DMA_PERIPHERAL_INC_DISABLE;
/* Reset Circular Mode*/
dmaConfig.loopMode = DMA_MODE_CIRCULAR;
/* set priority*/
dmaConfig.priority = DMA_PRIORITY_HIGH;
/* read from peripheral*/
dmaConfig.dir = DMA_DIR_PERIPHERALTOMEMORY;
/* Set memory Address*/
dmaConfig.memoryBaseAddr = (uint32_t)Buf;
/* Set Peripheral Address*/
dmaConfig.peripheralBaseAddr = (uint32_t)&ADC->CDATA;
dmaConfig.channel = DMA_CHANNEL_0;
dmaConfig.fifoMode = DMA_FIFOMODE_ENABLE;
dmaConfig.fifoThreshold = DMA_FIFOTHRESHOLD_HALFFULL;
dmaConfig.peripheralBurst = DMA_PERIPHERALBURST_SINGLE;
dmaConfig.memoryBurst = DMA_MEMORYBURST_SINGLE;
DMA_Config(DMA2_Stream0, &dmaConfig);
NVIC_EnableIRQRequest(DMA2_STR0_IRQn, 0x01, 0x01);
/* Clear DMA TF flag*/
DMA_ClearIntFlag(DMA2_Stream0, DMA_INT_TCI**0);
/* Enable DMA Interrupt*/
DMA_EnableInterrupt(DMA2_Stream0,DMA_INT_TCI**);
DMA_Enable(DMA2_Stream0);
}开启DMA中断，可以在每轮采样完成后进行数据处理
void DMA_IRQHandler(void)
{
if(DMA_ReadIntFlag(DMA2_Stream0,DMA_INT_TCI**0) != RESET)
{
APM_MINI_LEDToggle(LED2);
ADC1_CH0_ConvertedValue = (float)DMA_DualConvertedValue[0]/4095*3.3f;
ADC2_CH5_ConvertedValue = (float)DMA_DualConvertedValue[1]/4095*3.3f;
ADC3_CH10_ConvertedValue = (float)DMA_DualConvertedValue[2]/4095*3.3f;
ADC1_CH1_ConvertedValue = (float)DMA_DualConvertedValue[3]/4095*3.3f;
ADC2_CH6_ConvertedValue = (float)DMA_DualConvertedValue[4]/4095*3.3f;
ADC3_CH11_ConvertedValue = (float)DMA_DualConvertedValue[5]/4095*3.3f;
ADC1_CH2_ConvertedValue = (float)DMA_DualConvertedValue[6]/4095*3.3f;
ADC2_CH8_ConvertedValue = (float)DMA_DualConvertedValue[7]/4095*3.3f;
ADC3_CH12_ConvertedValue = (float)DMA_DualConvertedValue[8]/4095*3.3f;
ADC1_CH4_ConvertedValue = (float)DMA_DualConvertedValue[9]/4095*3.3f;
ADC2_CH9_ConvertedValue = (float)DMA_DualConvertedValue[10]/4095*3.3f;
ADC3_CH13_ConvertedValue = (float)DMA_DualConvertedValue[11]/4095*3.3f;
DMA_ClearIntFlag(DMA2_Stream0,DMA_INT_TCI**0);
}
}最后可以使用串口打印，输出采的电压。
int main(void)
{
USART_Config_T usartConfigStruct;
/* USART configuration */
USART_ConfigStructInit(&usartConfigStruct);
usartConfigStruct.baudRate = 115200;
usartConfigStruct.mode = USART_MODE_TX_RX;
usartConfigStruct.parity = USART_PARITY_NONE;
usartConfigStruct.stopBits = USART_STOP_BIT_1;
usartConfigStruct.wordLength = USART_WORD_LEN_8B;
usartConfigStruct.hardwareFlow = USART_HARDWARE_FLOW_NONE;
APM_MINI_LEDInit(LED2);
/* COM1 init*/
APM_MINI_COMInit(COM1, &usartConfigStruct);
DMA_Init((uint32_t*)DMA_DualConvertedValue);
ADC_Init();
while (1)
{
Delay(0x1FFFFF);
printf("\r\nADC CH0: ADC1 Voltage = %f V \r\n", ADC1_CH0_ConvertedValue);
printf("ADC CH1: ADC1 Voltage = %f V \r\n", ADC1_CH1_ConvertedValue);
printf("ADC CH2: ADC1 Voltage = %f V \r\n", ADC1_CH2_ConvertedValue);
printf("ADC CH4: ADC1 Voltage = %f V \r\n", ADC1_CH4_ConvertedValue);
printf("ADC CH5: ADC2 Voltage = %f V \r\n", ADC2_CH5_ConvertedValue);
printf("ADC CH6: ADC2 Voltage = %f V \r\n", ADC2_CH6_ConvertedValue);
printf("ADC CH8: ADC2 Voltage = %f V \r\n", ADC2_CH8_ConvertedValue);
printf("ADC CH9: ADC2 Voltage = %f V \r\n", ADC2_CH9_ConvertedValue);
printf("ADC CH10: ADC2 Voltage = %f V \r\n", ADC3_CH10_ConvertedValue);
printf("ADC CH11: ADC2 Voltage = %f V \r\n", ADC3_CH11_ConvertedValue);
printf("ADC CH12: ADC2 Voltage = %f V \r\n", ADC3_CH12_ConvertedValue);
printf("ADC CH13: ADC2 Voltage = %f V \r\n", ADC3_CH13_ConvertedValue);
}
}将PA0接到高电平，查看串口打印的就是正确的了。
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