MicoAir743 User Manual

Product Overview

MicoAir743 is an H743-based flight controller designed by MicoAir for multirotors and autonomous aircraft. It uses a 480 MHz STM32H743VIT6 processor and integrates a BMI088 + BMI270 dual-IMU configuration, a DPS310 barometer, an onboard IST8310 magnetometer, an AT7456E analog OSD chip, and a microSD card slot for flight logs.

The flight controller provides seven UARTs, 10 PWM outputs, one CAN bus, one I²C bus, 5 V / 3 A and 9 V / 3 A BEC outputs, and a connector for DJI O3/O4 digital video systems. It supports open-source firmware including ArduPilot, PX4, INAV, and Betaflight.

Key Features

• STM32H743VIT6, 480 MHz, 2 MB Flash
• BMI088 + BMI270 dual-IMU configuration
• DPS310 barometer and onboard IST8310 magnetometer
• AT7456E analog OSD
• Seven UARTs, 10 PWM outputs, one CAN bus, and one I²C bus
• microSD card slot for flight logs
• DJI O3/O4 digital video connector with DisplayPort support
• 5 V / 3 A and 9 V / 3 A BEC outputs
• 2–6S battery input, 6–27 V
• Supports ArduPilot, PX4, INAV, and Betaflight

Where to Buy

• MicoAir Tech Store

Hardware Specifications

Processor and Sensors

Interfaces and Outputs

Power and Mechanical Specifications

Dimensions and Installation

1. Mount the flight controller using the 30.5 × 30.5 mm hole pattern. Ensure that screws, metal washers, and the frame do not contact components on the board.
2. Vibration-damping standoffs are recommended. Tighten all fasteners evenly to avoid bending the board.
3. Keep the flight controller orientation marker pointing toward the nose of the aircraft. If the board must be rotated, configure the correct board orientation in the firmware.

Calibrate the accelerometer and magnetometer after all wiring is complete. If the positions of the battery leads, video transmitter, or propulsion system are changed, check for magnetic interference again.

Connectors and Power

Connector Layout

Typical Wiring

Power Requirements

Pin 1 of the SH1.0-6P digital video connector supplies 9 V. Before connecting a DJI O3/O4 or another video system, verify the pin order. Never connect this 9 V pin to an RC receiver, GNSS receiver, or camera that supports only 5 V.

Serial communication normally requires TX, RX, and GND. Connect the flight controller TX to the peripheral RX, and the flight controller RX to the peripheral TX. For a one-way protocol, connect only the signal line required by that protocol.

Serial Port Mapping

UART2 is shared with the DJI O3/O4 digital video connector. When DisplayPort is enabled, do not assign UART2 to another peripheral at the same time.

PWM Outputs

MicoAir743 provides up to 10 PWM outputs. PWM1–PWM10 support DShot, and PWM1–PWM8 support bidirectional DShot. Actual availability depends on the flight controller firmware and version.

PWM Timer Groups

Channels in the same timer group generally cannot use arbitrary combinations of output protocols. When changing the PWM frequency or DShot configuration, check every channel in the group together.

ESC Protocol Recommendations

• Standard PWM ESCs: Select a standard PWM protocol supported by the firmware.
• DShot ESCs: Start with DShot300 for a balance between reliability and bandwidth.
• Bidirectional DShot: Both the flight controller firmware and ESC firmware must support it. For PX4 and INAV, check the documentation for the firmware version in use.

Remove all propellers before testing the motors. Install the propellers only after verifying the motor numbering, rotation direction, and failsafe behavior.

RC Receiver

UART6 is the default RC input. Another available UART can also be configured for RC input, but only one port may be configured at a time.

If a CRSF/ELRS receiver is not detected, first verify that TX and RX are crossed, the supply voltage is correct, and UART6 is not assigned to another function.

OSD, Video Transmitter, and CAN

Analog OSD

• Onboard AT7456E
• In ArduPilot, set OSD_TYPE = 1 to enable the MAX7456-compatible driver
• Before use, verify the camera video standard, video input/output wiring, and firmware support

DisplayPort / DJI O3/O4

• The SH1.0-6P connector uses UART2 by default
• Supports MSP DisplayPort digital OSD
• The connector provides a 9 V power output

CAN

The flight controller provides one CAN bus for a CAN GNSS receiver, airspeed sensor, rangefinder, or other DroneCAN device.

Battery Monitoring, Magnetometer, and I²C

Battery Voltage and Current Monitoring

The current scaling factor depends on the current-sensing circuit of the connected ESC. The values in the table are the flight controller defaults. After installation, calibrate the readings against a multimeter or power meter.

Magnetometer and I²C

• Onboard magnetometer: IST8310
• An external magnetometer can be connected to the I²C SDA and SCL pins
• Keep an external GNSS receiver/magnetometer module away from battery leads, ESCs, and motors

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
• Officially supported since ArduPilot 4.6.0
• Firmware can be updated through MicoConfigurator or Mission Planner

Related links:

• Official ArduPilot hardware definition
• Official ArduPilot firmware downloads
• ArduPilot Custom Firmware Builder

PX4

• Firmware target: micoair_h743

• Officially supported since PX4 1.16.0

• Official PX4 hardware definition

• Official PX4 releases

• Historical MicoAir743 PX4 firmware

Official PX4 firmware build guide

Historical firmware source:

PX4-Autopilot at micoair743-v1.13.3

PX4-Autopilot at micoair743-v1.14.3

PX4-Autopilot at micoair743-v1.15.0

Bootloader build command:

make micoair_h743_bootloader

Firmware build command:

make micoair_h743_default

INAV

• Firmware target: MICOAIR743
• Officially supported since INAV 8.0.0
• Use the INAV Configurator version that matches the firmware version

Betaflight

• Firmware target: MICOAIR743
• Officially supported since Betaflight 4.5.0

Before enabling bidirectional DShot, verify that both the selected firmware target and ESC support it:

set dshot_bitbang = ON
save

Skybrush

• MicoAir743 can run Skybrush firmware for coordinated drone shows
• MicoAir743 Skybrush firmware

Always select the firmware target that exactly matches this board. Do not flash firmware for MicoAir743v2, MicoAir743-Lite, or any AIO model.

Firmware Flashing and Recovery

Normal Upgrade

1. Back up the current parameters.
2. Use MicoConfigurator, Mission Planner, or the appropriate firmware configurator to install a stable firmware release.
3. After flashing is complete, disconnect and reconnect power.

Entering DFU Mode

1. Disconnect both the battery and USB cable.
2. Press and hold the BOOT button.
3. While holding the button, connect the USB Type-C cable.
4. Release the button after the computer detects the DFU device.
5. On the DFU page in MicoConfigurator, select the correct target and flash the firmware.

In DFU mode, the flight controller does not appear as a serial port in Device Manager and its LEDs remain off. This is normal.

Troubleshooting

USB Connection Fails

• Use a known-good USB Type-C cable that supports data transfer
• Avoid an underpowered USB hub
• Check whether the operating system detects a serial port or DFU device
• Try entering DFU mode to verify that the hardware is detected

No Data from the GNSS Receiver, RC Receiver, or Video Transmitter

1. Verify that TX and RX are crossed and that the devices share a common ground.
2. Verify the peripheral supply voltage.
3. Check the serial protocol and baud rate.
4. Ensure that UART2 is not assigned to both DisplayPort and another device.

Battery Voltage or Current Is Inaccurate

• Compare the reported voltage with a multimeter reading
• Verify the ADC pins and default scaling values
• Calibrate BATT_CURR_SCALE according to the ESC current sensor specifications

Flight Controller Does Not Start After Flashing Incorrect Firmware

Hold BOOT while connecting USB to enter DFU mode, then select and flash the correct MicoAir743 target.

Related Resources

• MicoConfigurator
• Mission Planner
• ArduPilot documentation
• QGroundControl
• PX4 documentation
• Betaflight Configurator
• INAV Configurator

Appendix A: Pinout Table