GPIO

The GPIO module provides access to the GPIO pins of single board computers. See below for a list of supported boards that this module can be used with.

Permissions

A udev rule file is provided to simplify access permissions for GPIO pins.

First add the gpio group if it does not exist, then add the user running MQTTany to the gpio group:

sudo addgroup --system gpio
sudo usermod -aG gpio mqttany

Then install the udev rule and reboot:

sudo cp udev/98-gpio.rules /etc/udev/rules.d/
sudo reboot now

Paths

All pins configured in this module are available as properties of the node gpio. The state of a pin is available on the path gpio/{pin-id}.

Path	Description
`gpio/polling-interval`	The polling interval will be published here when the module starts, with `retained = True`.
`gpio/poll-all/set`	Sending any message (even blank) here will poll all configured pins and publish their states to their respective topics.
`gpio/{pin-id}`	Pin state will be published here.

Configuration

Optional settings are commented out with default values shown.

gpio:

  #mode: 'SOC'
  #polling interval: 60

  pin-id:
    pin:
    #name: '{pin_id}'
    #pin mode: 'input'
    #resistor: 'off'

  batch-id:
    pin: [  ]
    #name: '{pin_id}'
    #name: [  ]    # can also provide a matching list of names
    #first index: 0
    #pin mode: 'input'
    #resistor: 'off'

Module Settings

Option

Description

mode

GPIO numbering scheme, can be SOC (BCM), BOARD, or WIRINGPI. See the Supported Boards pages below for available pins and their number in each mode.

Optional, default SOC.

polling interval

Interval in seconds to publish all pin states.

Optional, default 60.

Single Pin Definition

Pin configuration section names must be unique as they are used as property IDs. Property IDs can only contain lowercase letters a-z, numbers 0-9, and hyphens -. The following settings are for single GPIO pin definitions:

Option	Description
`name`	Friendly name for the pin. Substitutions: `{pin}` will be replaced with the pin number `{pin:02d}` same as above, but will left pad the pin number with 0’s `{pin_id}` will be replaced with the pin definition section name. Optional, default `{pin_id}`.
`pin`	GPIO pin number.
`pin mode`	Pin mode, see available pins for options. Optional, default `input`.
`resistor`	Pin pull resistor for inputs, can be `pullup`, `pulldown` (if supported), or `off`. Optional, default `off`.

Multiple Pin Definition

It is also possible to define settings for several GPIO pins at the same time. Settings from single pin definitions apply here also, except those shown below.

Option

Description

pin

Instead of a single GPIO pin number you can specify a list of pins.

name

For multiple pin definitions, name can be a single name or a list of names the same length as the list of pins.

An additional substitution {index} is available when a list of pin numbers is given. It corresponds to the pin’s index in the list plus first index.

If a single name is given and the substitution {index} is not present, the name will have the index appended to the end like {name} {index}.

Optional, default {pin_id}.

first index

Will be added to pin number’s index in the list of pins when subsituting {index} in names. Ex. to start numbering at 1, set this to 1.

Optional, default 0.