ESP32 ADC多通道驱动 More...

#include <esp_adc.hpp>

Collaboration diagram for LibXR::ESP32ADC:

Data Structures
class	Channel
	ADC通道对象，提供通道级数据访问和抽象接口。 More...

Public Member Functions
	ESP32ADC (adc_unit_t unit, const adc_channel_t *channels, uint8_t num_channels, uint32_t freq=SOC_ADC_SAMPLE_FREQ_THRES_LOW, adc_atten_t attenuation=ADC_ATTEN_DB_12, adc_bitwidth_t bitwidth=static_cast< adc_bitwidth_t >(SOC_ADC_DIGI_MAX_BITWIDTH), float reference_voltage=3.3f, size_t dma_buf_size=256)
	构造函数：初始化ADC与DMA、参数配置 Constructor: Initialize ADC, DMA, and config parameters.

	~ESP32ADC ()
	析构函数，释放所有资源 Destructor. Free all resources and stop ADC.

Channel &	GetChannel (uint8_t idx)
	获取通道对象的引用 Get a reference to channel object by index.

float	ReadChannel (uint8_t idx)
	读取指定通道最新均值（已归一化为电压） Read latest averaged and normalized value (in volts) for the given channel.

Private Member Functions
void	HandleSamples (const void *buf, size_t size_bytes)
	采样缓冲区数据解析与均值计算 Parse DMA buffer and calculate channel averages.

float	Normalize (float raw) const
	原始ADC值归一化到电压 Normalize raw ADC value to voltage.

Static Private Member Functions
static bool IRAM_ATTR	OnConvDone (adc_continuous_handle_t handle, const adc_continuous_evt_data_t edata, void user_data)
	DMA采集完成中断回调。内部调用。 DMA conversion done callback. Called internally by ESP-IDF.

Private Attributes
adc_digi_pattern_config_t *	m_patterns_
	ADC采样模式数组 / Pattern config array.

Channel *	m_channels_
	通道对象数组 / Channel objects array

float *	m_latest_values_
	最新均值（每通道）/ Latest average value (per channel)

int *	m_sum_buf_
	求和缓冲 / Accumulation buffer

int *	m_cnt_buf_
	计数缓冲 / Count buffer

adc_unit_t	m_unit_
	ADC单元 / ADC unit.

uint8_t	m_num_channels_
	通道数 / Number of channels

adc_atten_t	m_attenuation_
	衰减档位 / Attenuation

adc_bitwidth_t	m_bitwidth_
	位宽 / Bit width

float	m_reference_voltage_
	参考电压 / Reference voltage

uint16_t	m_max_raw_
	最大原始采样值 / Max raw value

adc_continuous_handle_t	m_handle_ = nullptr
	ESP-IDF采集句柄 / ADC handle.

Detailed Description

ESP32 ADC多通道驱动

ESP32 multi-channel ADC driver

该类封装ESP32的ADC连续采样、DMA搬运和多通道均值计算。支持线程安全读取，适用于高采样率场景。

This class encapsulates ESP32 ADC continuous sampling, DMA buffering, and per-channel averaging. Thread-safe and suitable for high-speed applications.

Definition at line 33 of file esp_adc.hpp.

Constructor & Destructor Documentation

◆ ESP32ADC()

LibXR::ESP32ADC::ESP32ADC	(	adc_unit_t	unit,
		const adc_channel_t *	channels,
		uint8_t	num_channels,
		uint32_t	freq = SOC_ADC_SAMPLE_FREQ_THRES_LOW,
		adc_atten_t	attenuation = ADC_ATTEN_DB_12,
		adc_bitwidth_t	bitwidth = static_cast<adc_bitwidth_t>(SOC_ADC_DIGI_MAX_BITWIDTH),
		float	reference_voltage = 3.3f,
		size_t	dma_buf_size = 256 )

inline

构造函数：初始化ADC与DMA、参数配置 Constructor: Initialize ADC, DMA, and config parameters.

Parameters

unit	ADC单元（ADC_UNIT_1或2）/ ADC unit number (ADC_UNIT_1 or 2)
channels	ADC通道号数组 / Array of ADC channel numbers
num_channels	通道数量 / Number of channels
freq	采样频率（Hz）/ Sample frequency in Hz (default: SOC_ADC_SAMPLE_FREQ_THRES_LOW)
attenuation	衰减档位 / ADC attenuation (default: ADC_ATTEN_DB_12)
bitwidth	精度位宽 / Bit width (default: chip max)
reference_voltage	参考电压（V）/ Reference voltage (default: 3.3V)
dma_buf_size	DMA缓冲区大小 / DMA buffer size in bytes (default: 256)

Definition at line 98 of file esp_adc.hpp.

      : m_unit_(unit),
        m_num_channels_(num_channels),
        m_attenuation_(attenuation),
        m_bitwidth_(bitwidth),
        m_reference_voltage_(reference_voltage),
        m_max_raw_((1 << bitwidth) - 1)
  {
    m_patterns_ = new adc_digi_pattern_config_t[m_num_channels_];
    m_channels_ = new Channel[m_num_channels_];
    m_latest_values_ = new float[m_num_channels_];
    m_sum_buf_ = new int[m_num_channels_];
    m_cnt_buf_ = new int[m_num_channels_];
 
    for (uint8_t i = 0; i < m_num_channels_; ++i)
    {
      m_patterns_[i].atten = static_cast<uint8_t>(m_attenuation_);
      m_patterns_[i].channel = channels[i];
      m_patterns_[i].unit = static_cast<uint8_t>(m_unit_);
      m_patterns_[i].bit_width = static_cast<uint8_t>(m_bitwidth_);
      m_channels_[i] = Channel(this, i, channels[i]);
      m_latest_values_[i] = 0.f;
    }
 
    adc_continuous_handle_cfg_t adc_config = {
        .max_store_buf_size = dma_buf_size,
        .conv_frame_size = dma_buf_size / 2,
    };
    ESP_ERROR_CHECK(adc_continuous_new_handle(&adc_config, &m_handle_));
 
    adc_continuous_config_t dig_cfg = {};
    dig_cfg.sample_freq_hz = freq;
    if (m_unit_ == ADC_UNIT_1)
    {
      dig_cfg.conv_mode = ADC_CONV_SINGLE_UNIT_1;
    }
    else
    {
      dig_cfg.conv_mode = ADC_CONV_SINGLE_UNIT_2;
    }
    dig_cfg.format = XR_ADC_DMA_OUTPUT_TYPE;
    dig_cfg.adc_pattern = m_patterns_;
    dig_cfg.pattern_num = m_num_channels_;
    ESP_ERROR_CHECK(adc_continuous_config(m_handle_, &dig_cfg));
 
    adc_continuous_evt_cbs_t cbs = {
        .on_conv_done = &ESP32ADC::OnConvDone,
    };
    ESP_ERROR_CHECK(adc_continuous_register_event_callbacks(m_handle_, &cbs, this));
    ESP_ERROR_CHECK(adc_continuous_start(m_handle_));
  }

◆ ~ESP32ADC()

LibXR::ESP32ADC::~ESP32ADC ( )

inline

析构函数，释放所有资源 Destructor. Free all resources and stop ADC.

Definition at line 159 of file esp_adc.hpp.

  {
    if (m_handle_)
    {
      adc_continuous_stop(m_handle_);
      adc_continuous_deinit(m_handle_);
    }
    delete[] m_patterns_;
    delete[] m_channels_;
    delete[] m_latest_values_;
    delete[] m_sum_buf_;
    delete[] m_cnt_buf_;
  }

Member Function Documentation

◆ GetChannel()

Channel & LibXR::ESP32ADC::GetChannel ( uint8_t idx )

inline

获取通道对象的引用 Get a reference to channel object by index.

Parameters

idx	逻辑通道索引 / Channel logical index

Returns: Channel对象引用 / Reference to Channel object

Definition at line 179 of file esp_adc.hpp.

179{ return m_channels_[idx]; }

◆ HandleSamples()

void LibXR::ESP32ADC::HandleSamples	(	const void *	buf,
		size_t	size_bytes )

inlineprivate

采样缓冲区数据解析与均值计算 Parse DMA buffer and calculate channel averages.

Parameters

buf	缓冲区指针 / Buffer pointer
size_bytes	数据字节数 / Buffer size in bytes

Definition at line 210 of file esp_adc.hpp.

  {
    for (uint8_t idx = 0; idx < m_num_channels_; ++idx)
    {
      m_sum_buf_[idx] = 0;
      m_cnt_buf_[idx] = 0;
    }
 
    size_t n = size_bytes / sizeof(adc_digi_output_data_t);
    const adc_digi_output_data_t *samples =
        static_cast<const adc_digi_output_data_t *>(buf);
 
    for (size_t i = 0; i < n; ++i)
    {
      uint8_t ch = XR_ADC_DMA_GET_CHANNEL(&samples[i]);
      for (uint8_t idx = 0; idx < m_num_channels_; ++idx)
      {
        if (ch == m_channels_[idx].ChannelNumber())
        {
          int raw = XR_ADC_DMA_GET_DATA(&samples[i]);
          m_sum_buf_[idx] += raw;
          m_cnt_buf_[idx] += 1;
          break;
        }
      }
    }
 
    for (uint8_t idx = 0; idx < m_num_channels_; ++idx)
    {
      if (m_cnt_buf_[idx] > 0)
      {
        float avg = Normalize(static_cast<float>(m_sum_buf_[idx]) / m_cnt_buf_[idx]);
        m_latest_values_[idx] = avg;
      }
    }
  }

◆ Normalize()

float LibXR::ESP32ADC::Normalize ( float raw ) const

inlineprivate

原始ADC值归一化到电压 Normalize raw ADC value to voltage.

Parameters

raw	原始采样值 / Raw ADC value

Returns: 电压（V）/ Voltage (V)

Definition at line 254 of file esp_adc.hpp.

  {
    return (raw / static_cast<float>(m_max_raw_)) * m_reference_voltage_;
  }

◆ OnConvDone()

static bool IRAM_ATTR LibXR::ESP32ADC::OnConvDone	(	adc_continuous_handle_t	handle,
		const adc_continuous_evt_data_t *	edata,
		void *	user_data )

inlinestaticprivate

DMA采集完成中断回调。内部调用。 DMA conversion done callback. Called internally by ESP-IDF.

Definition at line 194 of file esp_adc.hpp.

  {
    auto *self = reinterpret_cast<ESP32ADC *>(user_data);
    self->HandleSamples(edata->conv_frame_buffer, edata->size);
    return false;
  }

◆ ReadChannel()

float LibXR::ESP32ADC::ReadChannel ( uint8_t idx )

inline

读取指定通道最新均值（已归一化为电压） Read latest averaged and normalized value (in volts) for the given channel.

Parameters

idx	逻辑通道索引 / Channel index

Returns: 电压值（V）/ Voltage value (V)

Definition at line 187 of file esp_adc.hpp.

187{ return m_latest_values_[idx]; }

Field Documentation

◆ m_attenuation_

adc_atten_t LibXR::ESP32ADC::m_attenuation_

private

衰减档位 / Attenuation

Definition at line 267 of file esp_adc.hpp.

◆ m_bitwidth_

adc_bitwidth_t LibXR::ESP32ADC::m_bitwidth_

private

位宽 / Bit width

Definition at line 268 of file esp_adc.hpp.

◆ m_channels_

Channel* LibXR::ESP32ADC::m_channels_

private

通道对象数组 / Channel objects array

Definition at line 260 of file esp_adc.hpp.

◆ m_cnt_buf_

int* LibXR::ESP32ADC::m_cnt_buf_

private

计数缓冲 / Count buffer

Definition at line 263 of file esp_adc.hpp.

◆ m_handle_

adc_continuous_handle_t LibXR::ESP32ADC::m_handle_ = nullptr

private

ESP-IDF采集句柄 / ADC handle.

Definition at line 271 of file esp_adc.hpp.

◆ m_latest_values_

float* LibXR::ESP32ADC::m_latest_values_

private

最新均值（每通道）/ Latest average value (per channel)

Definition at line 261 of file esp_adc.hpp.

◆ m_max_raw_

uint16_t LibXR::ESP32ADC::m_max_raw_

private

最大原始采样值 / Max raw value

Definition at line 270 of file esp_adc.hpp.

◆ m_num_channels_

uint8_t LibXR::ESP32ADC::m_num_channels_

private

通道数 / Number of channels

Definition at line 266 of file esp_adc.hpp.

◆ m_patterns_

adc_digi_pattern_config_t* LibXR::ESP32ADC::m_patterns_

private

ADC采样模式数组 / Pattern config array.

Definition at line 259 of file esp_adc.hpp.

◆ m_reference_voltage_

float LibXR::ESP32ADC::m_reference_voltage_

private

参考电压 / Reference voltage

Definition at line 269 of file esp_adc.hpp.

◆ m_sum_buf_

int* LibXR::ESP32ADC::m_sum_buf_

private

求和缓冲 / Accumulation buffer

Definition at line 262 of file esp_adc.hpp.

◆ m_unit_

adc_unit_t LibXR::ESP32ADC::m_unit_

private

ADC单元 / ADC unit.

Definition at line 265 of file esp_adc.hpp.

The documentation for this class was generated from the following file:

driver/esp/esp_adc.hpp

Data Structures

Public Member Functions

Private Member Functions

Static Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ ESP32ADC()

◆ ~ESP32ADC()

Member Function Documentation

◆ GetChannel()

◆ HandleSamples()

◆ Normalize()

◆ OnConvDone()

◆ ReadChannel()

Field Documentation

◆ m_attenuation_

◆ m_bitwidth_

◆ m_channels_

◆ m_cnt_buf_

◆ m_handle_

◆ m_latest_values_

◆ m_max_raw_

◆ m_num_channels_

◆ m_patterns_

◆ m_reference_voltage_

◆ m_sum_buf_

◆ m_unit_