SN74HC165 I/O Expander (shift register)¶
The SN74HC165 component allows you to use SN74HC165 shift registers as I/O expanders (Input only, use SN74HC595 for outputs) (datasheet) in ESPHome. It uses 3 wires (optionally 4) for communication.
Once configured, you can use any of the 8 pins for your projects. Up-to 256 shift registers can be daisy-chained to provide more pins, without using more GPIO pins on the controller. They are linked by connecting pin Q of the closer shift register to the pin QH of the next shift register.
# Example configuration entry sn74hc165: - id: sn74hc165_hub clock_pin: GPIO16 data_pin: GPIO17 load_pin: GPIO4 clock_inhibit_pin: GPIO18 sr_count: 2 # Individual inputs binary_sensor: - platform: gpio name: "SN74HC165 Pin #0" pin: sn74hc165: sn74hc165_hub # Use pin number 0 number: 0 inverted: false
id (Required, ID): The id to use for this SN74HC165 component.
data_pin (Required, Pin Schema): Pin connected to SN74HC165 Serial Output (QH) input.
clock_pin (Required, Pin Schema): Pin connected to SN74HC165 Clock (CLK) pin
load_pin (Required, Pin Schema): Pin connected to SN74HC165 Load input (SH/LD) pin
clock_inhibit_pin (Required, Pin Schema): Pin connected to SN74HC165 Clock Inhibit (CLK INH) pin
sr_count (Optional, int): Number of daisy-chained shift registers, up-to 256. Defaults to
Pin configuration variables:¶
SN74HC165 (Required, ID): The id of the SN74HC165 component of the pin.
number (Required, int): The pin number.
inverted (Optional, boolean): If received value should be treated as inverted. Defaults to
Pin number 0 is Pin A on the SN74HC165 that is furthest away from the microcontroller.