esphome::gpio_expander::CachedGpioExpander< T, N > Class Template Reference

A class to cache the read state of a GPIO expander. More...

#include <cached_gpio.h>

Public Member Functions
bool	digital_read (T pin)
	Read the state of the given pin.
void	digital_write (T pin, bool value)

Protected Member Functions
virtual bool	digital_read_hw (T pin)=0
	Call component low level function to read GPIO state from device.
virtual bool	digital_read_cache (T pin)=0
	Call component read function from internal cache.
virtual void	digital_write_hw (T pin, bool value)=0
	Call component low level function to write GPIO state to device.
void	reset_pin_cache_ ()
	Invalidate cache. This function should be called in component loop().

Protected Attributes
T	read_cache_valid_ [BANKS] {0}

Static Protected Attributes
static constexpr uint8_t	BITS_PER_BYTE = 8
static constexpr uint8_t	BANK_SIZE = sizeof(T) * BITS_PER_BYTE
static constexpr size_t	BANKS = N / BANK_SIZE
static constexpr size_t	CACHE_SIZE_BYTES = BANKS * sizeof(T)

Detailed Description

template<typename T, T N>
class esphome::gpio_expander::CachedGpioExpander< T, N >

A class to cache the read state of a GPIO expander.

This class caches reads between GPIO Pins which are on the same bank. This means that for reading whole Port (ex. 8 pins) component needs only one I2C/SPI read per main loop call. It assumes, that one bit in byte identifies one GPIO pin Template parameters: T - Type which represents internal register. Could be uint8_t or uint16_t. Adjust to match size of your internal GPIO bank register. N - Number of pins

Definition at line 19 of file cached_gpio.h.

Member Function Documentation

digital_read()

template<typename T , T N>

bool esphome::gpio_expander::CachedGpioExpander< T, N >::digital_read ( T pin )

inline

Read the state of the given pin.

This will invalidate the cache for the given pin number.

Parameters

pin	Pin number to read

Returns

Pin state

Definition at line 24 of file cached_gpio.h.

digital_read_cache()

template<typename T , T N>

virtual bool esphome::gpio_expander::CachedGpioExpander< T, N >::digital_read_cache ( T pin )

protectedpure virtual

Call component read function from internal cache.

Implemented in esphome::mcp23x08_base::MCP23X08Base, esphome::mcp23x17_base::MCP23X17Base, esphome::pi4ioe5v6408::PI4IOE5V6408Component, and esphome::tca9555::TCA9555Component.

digital_read_hw()

template<typename T , T N>

virtual bool esphome::gpio_expander::CachedGpioExpander< T, N >::digital_read_hw ( T pin )

protectedpure virtual

Call component low level function to read GPIO state from device.

Implemented in esphome::mcp23x08_base::MCP23X08Base, esphome::mcp23x17_base::MCP23X17Base, esphome::pi4ioe5v6408::PI4IOE5V6408Component, and esphome::tca9555::TCA9555Component.

digital_write()

template<typename T , T N>

void esphome::gpio_expander::CachedGpioExpander< T, N >::digital_write ( T pin, bool value )

inline

Definition at line 41 of file cached_gpio.h.

digital_write_hw()

template<typename T , T N>

virtual void esphome::gpio_expander::CachedGpioExpander< T, N >::digital_write_hw ( T pin, bool value )

protectedpure virtual

Call component low level function to write GPIO state to device.

Implemented in esphome::mcp23x08_base::MCP23X08Base, esphome::mcp23x17_base::MCP23X17Base, esphome::pi4ioe5v6408::PI4IOE5V6408Component, and esphome::tca9555::TCA9555Component.

reset_pin_cache_()

template<typename T , T N>

void esphome::gpio_expander::CachedGpioExpander< T, N >::reset_pin_cache_ ( )

inlineprotected

Invalidate cache. This function should be called in component loop().

Definition at line 52 of file cached_gpio.h.

Field Documentation

BANK_SIZE

template<typename T , T N>

uint8_t esphome::gpio_expander::CachedGpioExpander< T, N >::BANK_SIZE = sizeof(T) * BITS_PER_BYTE

staticconstexprprotected

Definition at line 55 of file cached_gpio.h.

BANKS

template<typename T , T N>

size_t esphome::gpio_expander::CachedGpioExpander< T, N >::BANKS = N / BANK_SIZE

staticconstexprprotected

Definition at line 56 of file cached_gpio.h.

BITS_PER_BYTE

template<typename T , T N>

uint8_t esphome::gpio_expander::CachedGpioExpander< T, N >::BITS_PER_BYTE = 8

staticconstexprprotected

Definition at line 54 of file cached_gpio.h.

CACHE_SIZE_BYTES

template<typename T , T N>

size_t esphome::gpio_expander::CachedGpioExpander< T, N >::CACHE_SIZE_BYTES = BANKS * sizeof(T)

staticconstexprprotected

Definition at line 57 of file cached_gpio.h.

read_cache_valid_

template<typename T , T N>

T esphome::gpio_expander::CachedGpioExpander< T, N >::read_cache_valid_[BANKS] {0}

protected

Definition at line 59 of file cached_gpio.h.

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

• esphome/components/gpio_expander/cached_gpio.h