Different protocols support different features. The details page of each protocol gives information specific to that protocol and its sub-protocols, including supported features, channel assignments, and any extra information.
Below are brief explanations of the features which protocols may have.
Auto-bind protocols bind automatically when the radio and receiver (or model) are powered on.
In OpenTX, enabling the Bind on Channel option in Model Setup disables binding at power-on, and instead requires an input to be configured to initiate binding.
Channel re-mapping automatically re-maps channels to the order required by the protocol - it assumes that the order specified in the Mixer or Outputs matches the expected channel order of the MULTI-Module.
Channel re-mapping is enabled by default for protocols which support it.
See the Channel Order page for more details.
With normal limits, the range of all outputs is -100% to +100%. Enabling Extended Limits increases this range to -150% to +150%.
Failsafe settings determine what the receiver will do if radio communication is lost. The receiver is configured using settings sent from the radio as part of the radio transmission.
Configuring failsafe settings ensures that the receiver behaves in an expected way if radio communications between the radio and receiver are lost, for example by reducing throttle to -100%, or activating a return-to-home (RTH or RTL) function in the flight controller.
Protocols which support failsafe:
Failsafe not configured.
Hold the last values received before radio communication was lost.
Use the radio to configure specific values for the receiver to use.
All channels go to their minimum values.
Use values configured on the receiver using the receiver's configured failsafe settings.
If a protocol supports Receiver Match, it is enabled by specifying a unique Receiver Number (RX Num) for each model in the Model Setup page, before binding the receiver. If the Receiver Number is changed the receiver will need to be re-bound to the radio.
Receiver Match can be disabled by assigning the same Receiver Number to all models. Receiver Number 0 is typically used for this purpose.
See the Receiver Match page for more information.
Telemetry enables the model or receiver to send information back to the radio,. Common uses are sending signal strength (RSSI) or flight battery voltage data so that it can be displayed on the radio.
Telemetry is also used to send information about the MULTI-Module (such as firmware version and channel order) to the radio.
All MULTI-Module telemetry, including sending module version and channel order information to the radio, can be disabled by checking the Disable Telemetry box in Model Setup.
The Disable Telemetry setting is intended for use in FrSky radios where it is necessary to disable MULTI-Module telemetry from an external MULTI-Module in order to allow telemetry from the internal module.
The Option Value may be used differently by each protocol. The use of Option Value is documented in each protocol's details page.
Low Power Mode reduces the transmission output power of the MULTI-Module to approximately 1/10th of normal output. It can be useful for:
Short-range testing (the power output is similar to the Range Test option)
Operating in an environment where reduced RF output is needed
Operating 'toy grade' models which normally use a low power transmitter and do not cope well with full power signals