Overview: Holybro Kakute F4 AIO V2

by Oscar

I have been asked multiple times about the new Holybro Kakute F4 AIO V2, what’s new in the new version, and how to wire up things. So I decided to make a post about it.

Some of the links on this page are affiliate links. I receive a commission (at no extra cost to you) if you make a purchase after clicking on one of these affiliate links. This helps support the free content for the community on this website. Please read our Affiliate Link Policy for more information.

The Kakute F4 AIO V2 is available at GetFPV, Banggood, Amazon. Here is my review of the V1 FC.

Update (Sep 2018): Holybro released an F7 board and you might want to consider it over the F4.

Update (July 2018): Holybro released the F7 version of the Kakute AIO FC.

The biggest change in the Kakute F4 AIO V2 is the pin layout, they rearranged it so it’s now a bit confusing for some people, also given the fact that they didn’t update the manual for a long time.

Kakute F4 AIO V1 Kakute F4 AIO V2

Differences between V1 and V2

Here is a summary of the differences:

  • 2 UART’s added in the V2 (5 vs 3)
    • Additional UART 4 for serial communication such as controlling the Runcam Split
    • Additional UART 5 RX for ESC telemetry, the pin is available at each corner of the board, next to ESC signals for easy wiring
  • Solder pads are replaced by through-holes, you can now solder on both sides of the board
  • Added Barometer sensor, making it a great option for Betaflight as well as iNav firmware
  • i2c pin-outs are available for external sensors such as GPS, making the Kakute a more versatile FC
  • Motor outputs have been reduced from 6 to 4

The rest of the spec are identical to the V1.

Some closeup shots of the V2:

Connection Diagram – Pin out

The connection is more or less the same as the Kakute F4 AIO V1. Anyway here is a list of pins and what they are used for.

B+ Battery positive voltage (2S-6S) 5V 1.5A max
VO Video output to VTX VI Video input from FPV camera
G Ground G Ground
SDA i2c SCL i2c
R3 UART 3 RX – inverted for SBUS T3 UART 3 TX
SP UART 1, inverted for SmartPort 5V 1.5A max
GND Ground 3V3 3.3V – 200mA max
RX5 UART 5 RX – ESC Telemetry
BUZ- Buzzer negative, connect positive to 5V


The Kakute F4 AIO V2 is available as a standalone FC, and it can now be purchased with other components as a bundle for a discount too:

Leave a Comment

By using this form, you agree with the storage and handling of your data by this website. Note that all comments are held for moderation before appearing.


Fred 7th January 2022 - 6:50 pm

I dont see anything in my goggles. I have the Kakute f4v2 A10 combo kit and have not been able to receive anything from my vtx to goggles. I am using Frsky R9m lite module and R9 mini receiver both running ELRS protocol not yhat tgat should matter.

Sergio Vial 25th September 2018 - 3:42 pm

Dear Oscar: I have the Kakute F4 V2 flashed with iNav firmware, the last one. My problem is to connect the Ublox 7m GPS to the board and be recognized by the inav. Do you know what is the best way to connect each other and how to configurate the GPS in iNav?

Goroth 26th July 2018 - 3:53 am

This is my first time building a drone so please forgive me if I as a stupid question.
I just bought the Holybro KAKUTE F4 AIO V2 and the Holybro Tekko32 35A 3-6S Blheli 32 4 In 1 ESC… BUT I don’t see any way to connect the ESC to the FC.
The ESC has M1, M2, M3, M4, Ctrl, VBAT
Yet on the AIO FC I don’t know where these go… Other than the VBAT

Is this possible or do I need to send back the ESC?

Gil 6th July 2018 - 11:40 pm

Is it possible to disable inversion on UART3?

Oscar 24th July 2018 - 5:54 pm

not really, it’s assigned for SBUS only.

kyle 24th April 2018 - 9:48 pm


kakute F4 and F4v2 is on there now

Nick 21st April 2018 - 12:14 am

Two questions if I may?
– How would you connect a TBS Nano Crsfx to the Kakute F4, via R3 and T3 for channel Outputs 1 & 2 and then then SDA and SCL to the equivalent ports on the F4?
– As kakute does not support PWM\PPM does that mean i don’t get the low latency link for crsfx, but instead get crsfx over SBUS?

Oscar 23rd April 2018 - 4:32 pm

– check out the connection diagram here: https://oscarliang.com/crossfire-betaflight/#connect-receiver
– The Crossfire doesn’t use PWM or PPM, it uses serial protocol called CRSF. It’s supported by the Kakute.

Max Jones 20th March 2018 - 2:06 pm

What port should I use for an ibus receiver? I think it is rx6 but I’m not quite sure.

Al 7th March 2018 - 3:30 am

Awww what a bummer they removed Motor 5 and 6 outputs.
I got this board to use with iNav because it has a baro and they added 2 UARTs and I2C.
But what a shame they removed motor 5 and 6 outputs..
I need those to control pitch on my brushless gimbal.
Any alternative to controlling the gimbal pitch using this board?

raul 27th February 2018 - 1:11 am

hello good I just got a kaute AIO F4 v2 and I have it mounted on the quad but it turns out that I have an X6B receiver mounted on theory I have it already connected to the station I also have it connected on the corresponding current pads and the signal cable on the RX3 pad. I have it in beta in the corresponding sections rx3, serial RX uart 3, ibus, when I connect the lipo the receiver remains a fixed light and the station I get the voltage values of the lipo also the problem is that they do not move bars in betaflight. Do you know what is the problem that I have?

Joe Doe 29th May 2018 - 6:09 am

I am having this same problem but am unable to figure it out. Any and vice and if you fixed it how did you do so? Thank you in advance.

Danny 2nd February 2018 - 7:22 am

Do you know if its possible to flash INAV?
as its a really great option.

Oscar 5th February 2018 - 2:42 pm

Yes it’s compatible with iNav, but i haven’t personally tried iNav yet.

Marcel 15th February 2018 - 8:45 pm

Do you have a Source for thats? I can’t found inav firmware for this Board.

Robert 25th January 2018 - 8:14 pm

I recently had a crash upgraded to this FC, and it is definitely very nice :-)