MicoAir743-Lite User Manual

Product Overview

The MicoAir743-Lite is a lightweight, high-performance H743 flight controller from MicoAir. It uses a 480 MHz STM32H743VIT6, an ICM45686 IMU with low temperature drift and high vibration tolerance, an SPA06 barometer, a microSD card slot for flight logs, and onboard Bluetooth telemetry connected to UART8.

The flight controller provides 8 UARTs, 15 PWM outputs, 1 I²C bus, 5 V / 2 A and 9 V / 2 A BEC outputs, and DisplayPort support for DJI O3/O4 digital video transmitters. It supports ArduPilot, PX4, and Betaflight firmware. INAV does not currently support this board because support for its ICM45686 IMU has not yet been implemented.

Key Features

• STM32H743VIT6, 480 MHz, 2 MB Flash
• ICM45686 IMU with BalancedGyro™ technology
• SPA06 barometer
• 8 UARTs, 15 PWM outputs, and 1 I²C bus
• PWM1–PWM8 support DShot and bidirectional DShot; availability depends on firmware support
• microSD card slot for flight logs
• Onboard Bluetooth telemetry connected to UART8 with a default baud rate of 115200
• DJI O3/O4/O4 Pro-compatible connector
• 5 V / 2 A and 9 V / 2 A BEC outputs
• 2–6S battery input, 6–27 V
• No onboard magnetometer or analog OSD

Where to Buy

• MicoAir Tech Store

Hardware Specifications

Processor and Sensors

Interfaces and Outputs

Power and Mechanical Specifications

Dimensions and Installation

1. Secure the flight controller using the 30.5 × 30.5 mm mounting pattern and vibration-damping standoffs.
2. Tighten the screws evenly. Do not bend the PCB or allow metal parts to touch board components.
3. Keep the flight-direction mark pointed toward the nose. If the board is installed at another orientation, configure the correct rotation in firmware.
4. Insert or remove the microSD card only while power is disconnected.

Connectors and Power

Connector Layout

Typical Wiring

Power Requirements

Pin 1 on the digital video connector is 9 V. Verify the pin order and peripheral input voltage before connecting a DJI O3/O4/O4 Pro.

Serial Port Mapping

UART8 is used by the onboard Bluetooth module at a default baud rate of 115200. UART2 is shared with the digital video DisplayPort connector.

PWM, ESCs, and Serial LEDs

The MicoAir743-Lite provides up to 15 PWM outputs. PWM1–PWM8 support DShot and bidirectional DShot. PWM15 shares its pin with the serial LED output.

PWM Timer Groups

When PWM15 is configured for a serial LED, PWM11 and PWM12 share the same timer-group constraints and may be limited to settings compatible with the serial LED output.

Remove all propellers before testing the motors. Start with DShot300; install the propellers only after verifying motor numbering, direction, and failsafe behavior.

RC Receiver

UART6 is the default RC input, although another unused UART can also be configured for the receiver.

OSD and Video Transmitter

The MicoAir743-Lite has no onboard analog OSD chip, but it supports DisplayPort OSD through the DJI O3/O4/O4 Pro digital video connector.

• The digital video connector uses UART2 by default
• Pin 1 on the connector provides 9 V
• OSD capability and configuration depend on the flight controller firmware and video transmitter firmware versions

Do not connect 9 V to a camera, receiver, or GNSS receiver that accepts only 5 V.

Battery Monitoring, Magnetometer, and I²C

Battery Monitoring

The current scaling factor depends on the current-sensing circuit in the ESC. Calibrate it after installation using a multimeter or power meter.

External Magnetometer

The board has no onboard magnetometer. Connect an external magnetometer to SDA / SCL over I²C.

Connecting to the Flight Controller over Bluetooth

The onboard Bluetooth module is connected to UART8 at a default baud rate of 115200. Android QGroundControl can use it to connect to ArduPilot or PX4.

Bluetooth is intended for short-range configuration and status monitoring on the ground.

Enable Bluetooth

1. Power the flight controller normally and wait at least 3 seconds.
2. Check the blue Bluetooth power indicator.
3. If the indicator is off, press and hold BOOT for approximately 2 seconds to enable Bluetooth.
4. Press and hold the button again to disable it. The setting is retained after power is removed.

Add a Connection in QGroundControl

Go to Application Settings → Comm Links and click Add.

Set the connection type to Bluetooth.

Click Scan and select the flight controller Bluetooth device whose name begins with MicoAir.

Older official tutorials may show a device name such as MicoAir743v2-xxxxx. Use the name detected by the phone and printed on the device label.

Select the device and click Connect. The green Bluetooth status indicator remains on after a successful connection.

QGroundControl loads the parameter list:

Flight Controller Firmware

MicoConfigurator is a browser-based flight controller configuration tool. It can configure flight controllers running ArduPilot or PX4 and update firmware online, from a local file, or in DFU mode.

ArduPilot

• Firmware target: MicoAir743-Lite

• Firmware can be updated through MicoConfigurator or Mission Planner

• Official ArduPilot hardware definition

• Official ArduPilot firmware downloads

• ArduPilot Custom Firmware Builder

• MicoAir743-Lite firmware repository

PX4

• Firmware target: micoair_h743-lite

• Firmware can be flashed with MicoConfigurator, downloaded from PX4 Releases, or built from source

• Official PX4 hardware definition

Official PX4 firmware build guide

Build the bootloader:

make micoair_h743-lite_bootloader

Build the default firmware:

make micoair_h743-lite_default

Betaflight

• MicoAir743-Lite Betaflight firmware

INAV

INAV does not currently support this board because support for its ICM45686 IMU has not yet been implemented.

Firmware Flashing and Recovery

Normal Upgrade

1. Back up the current parameters.
2. Select the correct target in MicoConfigurator, Mission Planner, or the applicable configurator.
3. After flashing, power-cycle the board and recheck the sensors, serial ports, and output settings.

Enter DFU Mode

1. Disconnect the battery and USB cable.
2. Press and hold BOOT.
3. While continuing to hold the button, connect USB Type-C.
4. Release the button after the DFU device is detected.
5. Flash the correct firmware from the DFU page in MicoConfigurator.

Troubleshooting

Bluetooth Device Not Found

• Wait at least 3 seconds after power-up, then press and hold BOOT for approximately 2 seconds
• Confirm that the blue power indicator is on
• Grant Android Bluetooth and Nearby devices permissions
• Confirm that UART8 uses 115200 baud and has not been reassigned
• Remove the old connection record and scan again

USB Connection Fails

• Use another USB Type-C cable that supports data transfer
• Try another USB port and avoid an underpowered hub
• Check whether a serial or DFU device appears

Motors Do Not Respond During Testing

• Confirm that the propulsion battery is connected
• Check output channels, frame type, and ESC protocol
• For Bluejay/AM32 ESCs, try DShot300 first
• Remove all propellers before testing

Board Does Not Boot After Flashing the Wrong Firmware

Hold BOOT while connecting USB to enter DFU mode, then select firmware for MicoAir743-Lite or micoair_h743-lite as appropriate.

Related Resources

• MicoConfigurator
• Flight Controller Firmware Flashing Guide
• ArduPilot Basic Setup Guide
• Connecting a MicoAir743v2/MicoAir743-Lite to a PC over Bluetooth
• Official ArduPilot documentation
• Official PX4 documentation
• QGroundControl Download and Install
• Betaflight Configurator

Appendix A: Pinout Table