MULTI-Module Firmware Downloads

From v1.3.4.0

Starting from MULTI-Module firmware version v1.3.4.0 the firmware files for 4-in-1 modules have changed because all protocols no longer fit in a single firmware image.

There are now four firmware type options:

• Air - includes core protocols plus protocols used in airborne craft.
• Surface - includes core protocols plus protocols used in ground or water craft
• FCC - includes surface, air, and EU/LBT protocols. Only available for CC2500 modules, where flash space permits all protocols to be included.
• EU (LBT) - includes all air and surface protocols which adhere to the European Union's Listen-Before-Talk directive and should be used in countries where this is required.

Notes:

• Air, Surface, and FCC firmware builds include both FCC and EU/LBT protocols.
• 'Core protocols' are the general purpose protocols for standalone receivers which could go in any type of craft and are included in both Air and Surface builds.
• If you require a combination of air and surface protocols you must compile your own firmware build using the instructions here.

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From v1.3.1.77

Starting from MULTI-Module firmware version v1.3.1.77 the firmware files have changed and some options are no longer required.

• No need to choose between OpenTX and erSkyTx/er9x builds because OpenTX/EdgeTX and erSkyTX/er9x now use the same method to receive telemetry data from the MULTI-Module.
• No need to choose between inverted and non-inverted telemetry because the radio and MULTI-Module will automatically negotiate the telemetry inversion setting

Firmware file names have been changed to reflect that these choices are no longer required.

The following minimum radio firmware versions are required in order to support these changes:

• OpenTX - 2.3.9
• erSkyTx - R223A4
• er9x - v822U