Backpack Documentation

Who should update from V1.4?

• MAVLink users
• Anyone looking to use Backpack for the MFD antenna trackers, or the DIY tracker
• Race timer backpack users
• Anyone with a ESP32C3 based backpack

New Features

MAVLink via WiFi for Backpack #141 #154

• Details: This update introduces MAVLink via UDP forwarding, along with a number of other flexible telemetry options. Telemetry mode is now configurable via LUA script with three states: - Off: Disables telemetry forwarding. - ESPNOW: Forwards telemetry (CRSF for now, MAVLink coming soon) via ESPNOW to the receiver, bypassing WiFi. - WiFi: Triggers WiFi on the Backpack for UDP forwarding of MAVLink telemetry to the Ground Control Station (GCS).

Support for ESP32C3 Based Backpacks #133

• Details: Backpack firmware can now run on the ESP32C3 microcontrollers. The ESP32C3 is a replacement for the end-of-life ESP8285 chip and offers other advantages.

Race Timer Backpack #114

• Details: Adds a backpack target for a generic race timer with the following features: - Ability to configure itself for sending messages to multiple pilot's backpacks as directed from the connected race timer. - Ability to start and stop races by monitoring for the MSP_ELRS_BACKPACK_SET_RECORDING_STATE only from the bound backpack (assuming race director's backpack) - The backpack was built to pair with this RotorHazard Plugin for sending OSD messages throughout the race to pilots with hardware to support it (HDZero goggles).

Automatic Antenna Tracker (AAT) backpack #126

• Details: Use an ESP8266/8285 backpack receiver, a couple of servos, and an optional screen, to build your own DIY antenna tracker that receives wireless telemetry data from an ExpressLRS TX module (assuming the TX has an onboard Backpack).

MFD Crossbow tracker integration #150

• Details: Introduces an integration with the MFD Crossbow and mini Crossbow antenna trackers, which wirelessly forwards the telemetry from an ELRS TX module to the Crossbow in order to track the craft. More details here: https://www.expresslrs.org/software/mfd-crossbow/

Other notable features

• WebUI enhancements #117
• Update power levels for wifi modes to full power #134

Bug Fixes

• Use the flashed bind phrase correctly #116
• Various build / flashing fixes

Targets

• RadioMaster Bandit TX backpacks
• BETAFPV SuperG backpack
• BetaFPV V2 Nano TX backpack
• iFlight V2 Commando 8 backpack
• Jumper T12 Max, T15 and T20 backpacks
• Race timer backpack receiver
• DIY AAT backpack receiver
• MFD Crossbow backpack receiver

A note on versioning

The versioning scheme chosen by the ExpressLRS devs is based on the semantic versioning scheme. Where a version is defined as “major.minor.patch” major = major new feature and/or incompatible changes minor = minor features or enhancements and/or new targets patch = bug-fixes