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Merge branch 'gpio_expander_fix_more_than_8_pins_in_bank' into optimize_pcf8574

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J. Nick Koston
2025-09-04 13:51:05 -05:00
parent 5b0d1fb30e e843f1759b
commit a63927a5f6
1 changed files with 9 additions and 4 deletions
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13
esphome/components/gpio_expander/cached_gpio.h
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@@ -11,11 +11,16 @@ namespace esphome::gpio_expander {
/// @brief 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
/// 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
/// T - Type which represents internal bank register. Could be uint8_t or uint16_t.
/// Choose based on how your I/O expander reads pins:
/// * uint8_t: For chips that read banks separately (8 pins at a time)
/// Examples: MCP23017 (2x8-bit banks), TCA9555 (2x8-bit banks)
/// * uint16_t: For chips that read all pins at once (up to 16 pins)
/// Examples: PCF8574/8575 (8/16 pins), PCA9554/9555 (8/16 pins)
/// N - Total number of pins (as uint8_t)
template<typename T, uint8_t N> class CachedGpioExpander {
public:
/// @brief Read the state of the given pin. This will invalidate the cache for the given pin number.