esphome-docs/components/sn74hc165.rst

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SN74HC165 I/O Expander (shift register)
=======================================
.. seo::
:description: Instructions for setting up SN74HC165 shift registers as digital port expanders in ESPHome.
The SN74HC165 component allows you to use SN74HC165 shift registers as I/O expanders (Input only, use SN74HC595 for outputs)
(`datasheet <https://www.ti.com/lit/ds/symlink/sn74hc165.pdf>`__) 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.
.. code-block:: yaml
# Example configuration entry
sn74hc165:
- id: sn74hc165_hub
clock_pin: GPIOXX
data_pin: GPIOXX
load_pin: GPIOXX
clock_inhibit_pin: GPIOXX
sr_count: 2
Configuration variables:
************************
- **id** (**Required**, :ref:`config-id`): The id to use for this SN74HC165 component.
- **data_pin** (**Required**, :ref:`Pin Schema <config-pin_schema>`): Pin connected to SN74HC165 Serial Output (QH) input.
- **clock_pin** (**Required**, :ref:`Pin Schema <config-pin_schema>`): Pin connected to SN74HC165 Clock (CLK) pin.
- **load_pin** (**Required**, :ref:`Pin Schema <config-pin_schema>`): Pin connected to SN74HC165 Load input (SH/LD) pin.
- **clock_inhibit_pin** (*Optional*, :ref:`Pin Schema <config-pin_schema>`): Pin connected to SN74HC165 Clock Inhibit (CLK INH) pin. The use of it is optional, as it can be directly connected to ground.
- **sr_count** (*Optional*, int): Number of daisy-chained shift registers, up-to 256. Defaults to ``1``.
Pin configuration variables:
****************************
.. code-block:: yaml
# Individual inputs
binary_sensor:
- platform: gpio
name: "SN74HC165 Pin #0"
pin:
sn74hc165: sn74hc165_hub
# Use pin number 0
number: 0
inverted: false
- **sn74hc165** (**Required**, :ref:`config-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 ``false``.
.. note::
Pin number 0 is Pin A on the SN74HC165 that is furthest away from the microcontroller.
See Also
--------
- :doc:`binary_sensor/gpio`
- :apiref:`SN74HC165/SN74HC165.h`
- :ghedit:`Edit`