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External notifications


The ExternalNotification Plugin will allow you to connect a speaker, LED or other device to notify you when a message has been received from the mesh network.


These are the settings that can be configured.

ext_notification_plugin_enabled    Is the plugin enabled?        0 = Disabled (Default)    1 = Enabled
ext_notification_plugin_active    Is your external circuit triggered when our GPIO is low or high?
    0 = Active Low (Default)    1 = Active High
ext_notification_plugin_alert_message    Do you want to be notified on an incoming message?
    0 = Disabled (Default)    1 = Alert when a text message comes
ext_notification_plugin_alert_bell    Do you want to be notified on an incoming bell?
    0 = Disabled (Default)    1 = Alert when the bell character is received
ext_notification_plugin_output    What GPIO is your external circuit attached?
    GPIO of the output. (Default = 13)
ext_notification_plugin_output_ms    How long do you want us to trigger your external circuit?
    Amount of time in ms for the alert. Default is 1000.

Usage Notes#

For basic usage, start with:

ext_notification_plugin_enabled = 1
ext_notification_plugin_alert_message = 1

Depending on how your external cirtcuit configured is configured, you may need to set the active state to true.

ext_notification_plugin_active = 1

The device must be restarted after the settings have been changed for the plugin to take effect.

Alert Types#

We support being alerted on two events:

1) Incoming Text Message

2) Incoming Text Message that contains the ascii bell character. At present, only the Python API can send an ascii bell character, but more support may be added in the future.

Bell Character#

The bell character is ASCII 0x07. Include 0x07 anywhere in the text message and with ext_notification_plugin_alert_bell enabled, we will issue an external notification.

External Hardware#

Be mindful of the max current sink and source of the esp32 GPIO. The easiest devices to interface with would be either an LED or Active Buzzer.

Ideas for external hardware:

  • LED
  • Active Buzzer
  • Flame thrower
  • Strobe Light
  • Siren

Known Problems#

  • This won't directly support an passive (normal) speaker as it does not generate any audio wave forms.
  • This currently only supports the esp32. Other targets may be possible, I just don't have to test with.
  • This plugin only monitors text messages. We won't trigger on any other packet types.