Sensor for reading the MCU analog input pins. More...

#include <sensesp/sensors/analog_input.h>

Inheritance diagram for sensesp::AnalogInput:

Public Member Functions
	AnalogInput (uint8_t pin=A0, unsigned int read_delay=200, const String &config_path="", float output_scale=1024.)

virtual	~AnalogInput ()

virtual bool	to_json (JsonObject &root) override

virtual bool	from_json (const JsonObject &config) override

Public Member Functions inherited from sensesp::Sensor< T >
	Sensor (String config_path)

Public Member Functions inherited from sensesp::SensorConfig
	SensorConfig (const String &config_path)

Public Member Functions inherited from sensesp::Observable
	Observable ()

	Observable (Observable &&other)
	Move constructor.

void	notify ()

int	attach (std::function< void()> observer)
	Attach an observer callback.

void	detach (int id)
	Remove a previously attached observer by its ID.

Public Member Functions inherited from sensesp::FileSystemSaveable
	FileSystemSaveable (const String &config_path)

virtual bool	load () override
	Load and populate the object from a persistent storage.

virtual bool	save () override
	Save the object to a persistent storage.

virtual bool	clear () override
	Delete the data from a persistent storage.

bool	find_config_file (const String &config_path, String &filename)

Public Member Functions inherited from sensesp::Saveable
	Saveable (const String &config_path)

virtual bool	refresh ()
	Refresh the object. This may or may not access the persistent storage but is not expected to overwrite the object's state.

const String &	get_config_path () const

Public Member Functions inherited from sensesp::ValueProducer< T >
	ValueProducer ()

	ValueProducer (const T &initial_value)

virtual const T &	get () const

template<typename VConsumer >
std::enable_if< std::is_base_of< ValueConsumer< typenameVConsumer::input_type >, VConsumer >::value &&std::is_convertible< T, typenameVConsumer::input_type >::value, std::shared_ptr< VConsumer > >::type	connect_to (std::shared_ptr< VConsumer > consumer)
	Connect a producer to a transform with a different input type.

template<typename VConsumer >
std::enable_if< std::is_base_of< ValueConsumer< typenameVConsumer::input_type >, VConsumer >::value &&std::is_convertible< T, typenameVConsumer::input_type >::value, VConsumer * >::type	connect_to (VConsumer *consumer)

template<typename VConsumer >
std::enable_if< std::is_base_of< ValueConsumer< typenameVConsumer::input_type >, VConsumer >::value &&std::is_convertible< T, typenameVConsumer::input_type >::value, VConsumer * >::type	connect_to (VConsumer &consumer)

void	emit (const T &new_value)

Protected Member Functions
void	update ()

Protected Attributes
uint8_t	pin_ {}

unsigned int	read_delay_

float	output_scale_

std::unique_ptr< BaseAnalogReader >	analog_reader_ {}

reactesp::RepeatEvent *	repeat_event_ = nullptr

Protected Attributes inherited from sensesp::Saveable
const String	config_path_

Protected Attributes inherited from sensesp::ValueProducer< T >
T	output_

Detailed Description

Sensor for reading the MCU analog input pins.

Read an analog input pin at regular intervals and return the result scaled onto a given range. The reading is calibrated in millivolts using the Arduino core's analogReadMilliVolts(), so it compensates for the ESP32 ADC's nonlinearity. The ADCs are still noisy; for high accuracy, SensESP supports the ADS1015 and ADS1115 ADCs.

Unlike RepeatSensor, AnalogInput can expose its read delay in the web configuration UI. Give it a config_path and pass it to ConfigItem() if you want to adjust the read interval at run time.

Parameters

[in]	pin	The GPIO pin to read. Which pins are usable depends on the ESP32 variant. Note that pins on ADC2 cannot be read while Wi-Fi is active, which in practice limits you to ADC1 pins (GPIO 32..39 on the original ESP32).
[in]	read_delay	Time delay between consecutive readings, in ms
[in]	config_path	Configuration path for the sensor
[in]	output_scale	The scale of the converted input value that AnalogInput produces. The raw value width of the ADC varies between ESP32 variants, so AnalogInput normalizes the calibrated input voltage against a 3.3 V full-scale reference and multiplies that fraction by 'output_scale'. Output is therefore in the range 0 to 'output_scale', and the same code behaves identically across variants. The default value is 1024. If you want your output expressed as a percentage, make this parameter 100. If you want the actual voltage at the pin, make it 3.3 – that holds regardless of the ADC attenuation set with analogSetAttenuation(), because the reading is calibrated in millivolts before it is scaled. If you want the voltage on the input side of a physical voltage divider, make this parameter the voltage that the divider maps onto the pin's full-scale range.

Definition at line 48 of file analog_input.h.

Constructor & Destructor Documentation

◆ AnalogInput()

sensesp::AnalogInput::AnalogInput	(	uint8_t	pin = `A0`,
		unsigned int	read_delay = `200`,
		const String &	config_path = `""`,
		float	output_scale = `1024.`
	)

Definition at line 10 of file analog_input.cpp.

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◆ ~AnalogInput()

virtual sensesp::AnalogInput::~AnalogInput ( )

inlinevirtual

Definition at line 53 of file analog_input.h.

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Member Function Documentation

◆ from_json()

bool sensesp::AnalogInput::from_json ( const JsonObject & root )

overridevirtual

Deserializes the current object data from a JsonObject.

Reimplemented from sensesp::Serializable.

Definition at line 34 of file analog_input.cpp.

◆ to_json()

bool sensesp::AnalogInput::to_json ( JsonObject & root )

overridevirtual

Serializes the current object data into a JsonObject.

Reimplemented from sensesp::Serializable.

Definition at line 29 of file analog_input.cpp.

◆ update()

void sensesp::AnalogInput::update ( )

protected

Definition at line 25 of file analog_input.cpp.

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Member Data Documentation

◆ analog_reader_

std::unique_ptr<BaseAnalogReader> sensesp::AnalogInput::analog_reader_ {}

protected

Definition at line 66 of file analog_input.h.

◆ output_scale_

float sensesp::AnalogInput::output_scale_

protected

Definition at line 65 of file analog_input.h.

◆ pin_

uint8_t sensesp::AnalogInput::pin_ {}

protected

Definition at line 63 of file analog_input.h.

◆ read_delay_

unsigned int sensesp::AnalogInput::read_delay_

protected

Definition at line 64 of file analog_input.h.

◆ repeat_event_

reactesp::RepeatEvent* sensesp::AnalogInput::repeat_event_ = nullptr

protected

Definition at line 67 of file analog_input.h.

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

src/sensesp/sensors/analog_input.h
src/sensesp/sensors/analog_input.cpp

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ AnalogInput()

◆ ~AnalogInput()

Member Function Documentation

◆ from_json()

◆ to_json()

◆ update()

Member Data Documentation

◆ analog_reader_

◆ output_scale_

◆ pin_

◆ read_delay_

◆ repeat_event_