Holybro Kakute F4 V2.4 Flight Controller

Overview

The Holybro Kakute F4 V2.4 Flight Controller is designed for FPV drones, offering plug-and-play compatibility with DJI O3 HD camera systems, 4in1 ESCs, and various peripherals. It features an integrated barometer for autonomous flight, an OSD chip, 5x UARTs, and onboard flash for logging.

The flight controller supports analog camera systems and includes an on-board 9V/3A regulator for powering HD video transmitters like DJI O3 Air Unit and Caddx Vista. It also provides a 5V/2A BEC for other peripherals.

Key Features:

• MCU: STM32F405
• IMU: MPU6000
• Barometer: BMP280
• OSD: AT7456E
• 5x UARTs (1,3,4,5,6)
• 128 Mbit Dataflash chip
• Input Voltage: 2S - 8S
• BEC 9V/3A - Optimized for DJI O3 Air unit
• BEC 5V/2A
• 7x PWM Outputs (6 Motor Output, 1 LED)
• Supports serial receivers (SBUS, iBus, Spektrum, Crossfire, ELRS)
• Mounting: 30.5 x 30.5mm, with M3 Grommets
• Dimensions: 37 x 37mm
• Weight: 7g
• JST-SH1.0_8pin port (For 4in1 ESCs)
• JST-SH1.0_6pin port (For DJI/Caddx HD System and other VTX)

Pinout Diagram

The Kakute F4 V2.4 has clearly labeled pins for various functions:

JST SH 8 Pin Port:

The 8PIN SH connector can be used to connect directly to compatible 4-in-1 ESCs. Some pins are only present in the SH connector, not as pads on the board.

JST SH 6 Pin Port:

The 6PIN SH port is convenient for connecting the Holybro Kakute F4 V2 to the DJI O3 Air Unit or Caddx Vista, or other VTX for signal and power supply.

Wiring Diagram

The Kakute F4 V2.4 supports various wiring configurations for different FPV systems.

Using DJI/Caddx Digital FPV System with DJI Remote Controller

Note: For OSD information to be sent to the Air Unit/Vista, UART1 must be set to MSP. If using DJI Remote Controller, set Serial Rx on for UART 3. Ensure your Receiver Protocol is set to SBUS.

Connections:

• Air Unit: GND, 9V, TX, RX
• DJI O3 Air Unit: GND, 9V, TX, RX
• Receiver (SBUS): SBUS, GND, 5V, TX, RX

Video Transmitter (Vtx) (If not using DJI/Caddx Digital System)

Connect the VTX to the appropriate pads on the flight controller, typically involving Video signal, GND, and power (5V or B+).

• TBS UNIFY PRO HV/NANO: Video, GND, TBS Smartaudio/CRSF
• Atlatl HV V2: Video, GND, 5V

GPS

Connect the GPS module using the SDA, SCL, TXD, RXD, VCC, and GND pins. Ensure correct UART configuration in Betaflight.

Buzzer/LED

Connect the buzzer to the Buzzer pad and the addressable LED to the LED pad (WS2812).

Analog FPV Camera

Connect the analog FPV camera to the VI (Video Input) and GND pads. Power is supplied via the 5V pad.

Installing a Receiver (If you are not using the DJI Remote Controller)

Note: If not using the DJI Remote Controller, do not connect the SBUS and GND wires to the Air Unit.

Follow the diagrams and instructions to set up your receiver:

TBS Crossfire, Tracer or ELRS

Connect the receiver's TX to the flight controller's RX pad (e.g., UART3 RX) and GND to GND. For CRSF protocol, select CRSF as the Serial Receiver Provider.

FrSky R-XSR

Connect SBUS IN to the appropriate RX pad (e.g., UART4 RX) and GND to GND. For SBUS protocol, select SBUS as the Serial Receiver Provider. For F.Port, connect to the SmartPort pad and select FPORT as the Serial Receiver Provider.

CLI Commands for F.Port:

set serialrx_provider=FPORT
set serialrx_inverted=ON
set serialrx_halfduplex=ON
save

ESCs

Plug-and-Play 4in1 ESC Ports

The Kakute F4 V2.4 is compatible with 4-in-1 ESCs. Connect the 8-pin JST SH connector from the ESC to the flight controller. The connections include:

• B+: Battery Positive Voltage (2S-6s)
• R5: UART5 R5 (ESC Telemetry)
• GND: Ground
• CUR: Current Sensor
• M1, M2, M3, M4: Motor Signal outputs