STM32 LL库踩坑系列三（ADC测电压或外部温度传感器）

STM32 LL库踩坑系列三（ADC测电压或外部温度传感器）

这个作者很懒，想到什么就写什么！

写在前面：这个是记录学习LL库的踩坑系列，这个资料很少，想要找例程可以在电脑用户文件下的STM32Cube\Repository里，前提是下载好那个单片机的pack，部分没有例程的可以借鉴同系列的文件。

本次使用DMA读取2个GPIO口的脚的ADC采集值。使用cubemx配置如下 采样的时钟频率一般情况下不宜太小或者太大，对应实际硬件。 生成LL库代码后添加

DMA添加代码 主要有读取后保存的地址和启动DMA

/* Definition of ADCx conversions data table size */ #define ADC_CONVERTED_DATA_BUFFER_SIZE ((uint32_t) 4) /* Variables for ADC conversion data */ __IO uint16_t aADCxConvertedData[ADC_CONVERTED_DATA_BUFFER_SIZE]; /* ADC group regular conversion data */ void Activate_DMA(void) { /* Set DMA transfer addresses of source and destination */ LL_DMA_ConfigAddresses(DMA2, LL_DMA_STREAM_0, LL_ADC_DMA_GetRegAddr(ADC1, LL_ADC_DMA_REG_REGULAR_DATA), (uint32_t)&aADCxConvertedData, LL_DMA_DIRECTION_PERIPH_TO_MEMORY); /* Set DMA transfer size */ LL_DMA_SetDataLength(DMA2, LL_DMA_STREAM_0, ADC_CONVERTED_DATA_BUFFER_SIZE); /*## Activation of DMA #####################################################*/ /* Enable the DMA transfer */ LL_DMA_EnableStream(DMA2,LL_DMA_STREAM_0); }

ADC添加代码 主要为启动ADC和使能转换

void Activate_ADC(void) { /*## Operation on ADC hierarchical scope: ADC instance #####################*/ /* Note: Hardware constraint (refer to description of the functions */ /* below): */ /* On this STM32 serie, setting of these features are not */ /* conditioned to ADC state. */ /* However, in order to be compliant with other STM32 series */ /* and to show the best practice usages, ADC state is checked. */ /* Software can be optimized by removing some of these checks, if */ /* they are not relevant considering previous settings and actions */ /* in user application. */ // if (LL_ADC_IsEnabled(ADC1) == 0) { /* Enable ADC */ LL_ADC_Enable(ADC1); /* Start ADC group regular conversion */ LL_ADC_REG_StartConversionSWStart(ADC1); LL_ADC_REG_SetDMATransfer(ADC1,LL_ADC_REG_DMA_TRANSFER_UNLIMITED); } /*## Operation on ADC hierarchical scope: ADC group regular ################*/ /* Note: No operation on ADC group regular performed here. */ /* ADC group regular conversions to be performed after this function */ /* using function: */ /* "LL_ADC_REG_StartConversion();" */ /*## Operation on ADC hierarchical scope: ADC group injected ###############*/ /* Note: No operation on ADC group injected performed here. */ /* ADC group injected conversions to be performed after this function */ /* using function: */ /* "LL_ADC_INJ_StartConversion();" */ }

电压转换

/* Definitions of environment analog values */ /* Value of analog reference voltage (Vref+), connected to analog voltage */ /* supply Vdda (unit: mV). */ #define VDDA_APPLI ((uint32_t)3300) /* 计算电压 */ vdd = __LL_ADC_CALC_DATA_TO_VOLTAGE(VDDA_APPLI, aADCxConvertedData[1], LL_ADC_RESOLUTION_12B);

温度转换需要根据实际使用热敏电阻的规则，使用查表的方式比较得出。