MicoAir H743 V2 Flight Controller — User Manual
The MicoAir H743 V2 (board name: MicoAir743v2) is a high-performance 30.5×30.5 flight controller built around the STM32H743 processor with dual IMUs (BMI088 + BMI270), a built-in Bluetooth telemetry module, and native support for all four major open-source firmwares: ArduPilot, PX4, INAV, and Betaflight. It is the flagship flight controller in the Robofusion lineup and the board we recommend for most ArduPilot builds.
Where to buy
- Robofusion store (ships from Canada — free Canada-wide shipping): MicoAir H743 V2 Flight Controller — available as FC only, or as a stack with a 50 A / 70 A AM32 4-in-1 ESC
A flight controller (FC) is the drone's brain: it reads motion sensors (the IMU — gyroscope + accelerometer) hundreds of times per second, figures out which way the aircraft is tilting, and adjusts each motor's speed to keep it stable. Everything else connects to it — GPS, receiver, video transmitter, telemetry radio. Two spec letters matter most when choosing one: F4 vs H7 describes the processor generation (H7 is roughly 3× faster with 2× the memory — headroom for logging, scripting, and future firmware versions), and the IMU model determines how clean the motion data is. The H743 V2 pairs the fast processor with two independent IMUs, so the firmware can cross-check them and keep flying even if one misbehaves.
H743 V2, F405 V2, or NxtPX4 V2 — which one?
| H743 V2 | F405 V2 | NxtPX4 V2 | |
|---|---|---|---|
| Processor | STM32H743, 480 MHz | STM32F405, 168 MHz | STM32H743, 480 MHz |
| IMU | BMI088 + BMI270 (dual) | BMI088 | BMI088 × 2 (dual) |
| Compass | Built-in QMC5883L | External (via I2C) | External (via I2C) |
| Firmware | ArduPilot / PX4 / INAV / Betaflight | ArduPilot / INAV | PX4 (native) / ArduPilot |
| UARTs / PWM | 8 / 11 | 6 / 10 | 7 / 8 |
| Bluetooth telemetry | Built-in | — | — |
| Mounting | 30.5 × 30.5 mm | 30.5 × 30.5 mm | 20 × 20 mm |
| Best for | Full-featured ArduPilot/PX4 builds, do-it-all choice | Budget long-range ArduPilot/INAV builds | Small research & VIO drones, PX4 labs |
Specifications
| Item | Specification |
|---|---|
| MCU | STM32H743VIT6, 480 MHz, 2 MB flash |
| IMU | BMI088 + BMI270 (dual, independent) |
| Barometer | SPL06 |
| Compass | QMC5883L (built-in) |
| OSD chip | AT7456E (analog OSD) |
| Logging | MicroSD card slot |
| Interfaces | 8× UART, 11× PWM, 1× I2C, 1× SWD, 2× ADC (voltage / current) |
| USB | Type-C |
| HD VTX connector | SH1.0-6P for DJI O3 / O4 Air Unit and other HD systems |
| BEC | 5 V 3 A (receiver, GPS, optical flow…) + 12 V 3 A (VTX, camera) |
| Bluetooth | Built-in module on UART8, 115200 baud |
| Battery input | 2–6S LiPo (6–27 V), on-board voltage sensing |
| Mounting | 30.5 × 30.5 mm, Φ4 mm holes |
| Dimensions / weight | 36 × 36 × 8 mm / 10 g |
Pinout
UART mapping
| Port | ArduPilot | PX4 | Default function |
|---|---|---|---|
| USB | SERIAL0 | ttyACM0 | GCS connection |
| UART1 | SERIAL1 | TELEM1 | MAVLink2 telemetry |
| UART2 | SERIAL2 | GPS2 | DisplayPort (HD VTX OSD) |
| UART3 | SERIAL3 | GPS1 | GPS |
| UART4 | SERIAL4 | TELEM2 | MAVLink2 (second radio / companion) |
| UART5 | SERIAL5 | TELEM3 | Spare (user) |
| UART6 | SERIAL6 | RC | RC receiver input |
| UART7 | SERIAL7 | — | ESC telemetry (RX only) |
| UART8 | SERIAL8 | TELEM4 | Built-in Bluetooth |
All UARTs are DMA-enabled, so any of them can run high-rate protocols without loading the CPU.
A UART is simply a two-wire serial port (TX = transmit, RX = receive). Every peripheral — GPS, receiver, telemetry radio, VTX — occupies one. Eight UARTs is the practical difference between "plug everything in" and "choose which two accessories you can live without" on cheaper boards.
RC input
UART6 (RX6/TX6) is the default RC port and works with all ArduPilot-supported protocols:
- SBUS / DSM / SRXL — connect to RX6
- CRSF / ELRS — connect both RX6 and TX6 (telemetry comes back automatically)
- FPort — connect TX6
- SRXL2 — connect TX6 and set
SERIAL6_OPTIONS = 4 - PPM is not supported on this board
OSD and HD VTX
Two OSD paths work simultaneously:
- Analog OSD — the onboard AT7456E chip (
OSD_TYPE = 1), used with analog VTX modules like the VT5804 / VT5805 - DisplayPort (HD) OSD — on the SH1.0-6P HD VTX connector (
OSD_TYPE2 = 5), for DJI O3/O4 and similar HD systems
Pin 1 of the SH1.0-6P connector carries the 12 V BEC rail for the video system. Never wire a 5 V peripheral to it.
PWM outputs and DShot
11 PWM outputs; channels 1–8 also support bi-directional DShot (ArduPilot/Betaflight; PX4 and INAV do not support BDShot on this board yet). Outputs are grouped — every output in a group must run the same protocol:
| Group | Outputs |
|---|---|
| 1 | 1, 2, 3, 4 |
| 2 | 5, 6 |
| 3 | 7, 8, 11 |
| 4 | 9, 10 |
PWM 11 doubles as the LED pin; if it is configured for serial LEDs, outputs 7 and 8 can only be used as serial LED outputs too.
Classic PWM sends motor commands as an analog pulse width — it works, but needs calibration and picks up noise. DShot sends the same command as a digital number, so there is nothing to calibrate and no drift. Bi-directional DShot additionally lets each ESC report motor RPM back to the FC, which enables RPM-based gyro filtering — noticeably smoother flight on ArduPilot and Betaflight.
Battery monitoring
Voltage sensing is built in (up to 6S); current sensing uses the signal from your 4-in-1 ESC via the ESC connector. Default ArduPilot parameters:
| Parameter | Value |
|---|---|
BATT_MONITOR | 4 |
BATT_VOLT_PIN | 10 |
BATT_CURR_PIN | 11 |
BATT_VOLT_MULT | 21.2 |
BATT_AMP_PERVLT | 40.2 |
After the first battery connection, verify the reported voltage against a battery checker and fine-tune BATT_VOLT_MULT if needed.
Compass
A QMC5883L compass is built in. In practice, most builders run an external compass on the GPS mast (connected via the SDA/SCL pads) and disable the internal one — the internal compass sits close to power wiring and picks up magnetic interference from motor current.
Bluetooth telemetry
The built-in Bluetooth module is wired to UART8 (115200 baud) and broadcasts as MicoAir743v2-xxxxxx — no pairing code needed. Connect from a phone or laptop GCS (QGroundControl, Mission Planner, or MicoPilot) for wireless parameter tuning without plugging in USB. For flying range, use a proper telemetry radio like the LR900 — Bluetooth is a bench-and-field-setup convenience, not a flight link.
Firmware
| Firmware | Support | Target / notes |
|---|---|---|
| ArduPilot | Official | Target MicoAir743v2 — stable builds on firmware.ardupilot.org |
| PX4 | Supported | Build target micoair_h743-v2_default |
| INAV | Official since 8.0 | Target MICOAIR743V2 |
| Betaflight | Manufacturer builds | micoair/MicoAir743v2 on GitHub |
First-time flashing (DFU)
- Hold the bootloader button, plug in USB — the board enumerates in DFU mode
- Flash the
arduXXXX_with_bl.hexfile with your DFU tool (or Mission Planner → Load custom firmware, or MicoConfigurator) - From then on, update normally over USB with
.apjfiles from any ArduPilot ground station — no button needed
FAQ
Which firmware should a beginner pick?
If you want GPS missions, autonomous flight and the biggest tuning community, choose ArduPilot. Pick INAV if you fly fixed-wing FPV, Betaflight for pure acro/racing quads, PX4 if your workflow depends on its ecosystem (offboard control, research tooling).
Does it work with both analog and digital (HD) FPV?
Yes, simultaneously if you like: analog VTX via the onboard OSD chip and video pads, HD systems (DJI O3/O4, etc.) via the dedicated HD VTX connector with DisplayPort OSD.
Why are two IMUs better than one?
The firmware runs both continuously and compares them. If one drifts from vibration, temperature, or damage, the other keeps the aircraft flying — and having two different sensor models (BMI088 + BMI270) means they don't share the same failure modes.
What ESC should I pair with it?
Any standard 4-in-1 ESC with a 30.5×30.5 mount. The matching option is the MicoAir 50 A or 70 A AM32 ESC — both available as a stack bundle on the product page.
Related guides
- F405 V2 Flight Controller — User Manual
- NxtPX4 V2 Flight Controller — User Manual
- ArduPilot — Telemetry Setup Guide
- VT5804 5.8 GHz 2.5W Video Transmitter — User Manual
Written and maintained by the Robofusion engineering team. Hardware reference data from MicoAir Tech and the ArduPilot documentation (CC BY-SA 3.0).