Hardware revisions of Omnibus F4 flight controllers

Airbot Omnibus F4 series is one of my favorite flight controllers. Two of my quads are flying thanks to them. They might not be the best or the famous ones, but they get the job done. And that is what counts.

Airbot Omnibus F4 v1

Unfortunately, they are not free of faults (and what is?) and each next revision is trying to fix some problems. Sometimes by introducing a new one. Right now, there are 4 hardware revisions, not always fully compatible with each other.

Omnibus F4 v4 flight controller

Here is a summary of all 4 revisions…

Continue reading Hardware revisions of Omnibus F4 flight controllers

GPS Racer: worklog #2

I'm once again realizing, that doing multiple things at once is not a way to work. Something like that happened to my GPS Racer project. According do original plans, week ago I was only supposed to wait for FPV camera.

Instead of that, only yesterday I finished ESC and motor assembly. But OK, it was a little trickier than I expected originally:

  1. Since I wanted to reuse onboard current meter of Airbot Omnibus F4 (v2) Pro and use Matek XT60 PDB at the same time, I had to do some creative wiring between XT60 plug and PDB. Instead of directly connecting XT60 plug to PDB, + first goes to current meter on Omnibus F4 Pro and then goes back to PDB. Not pretty, but works. I still have to design some kind for power plug holder, but this topic can wait. I still have no FPV camera
  2. I had some problems with ESCs. Not only I've destroyed Motor1 soldering pad, but failed to flash FVT Littlebee 30A with latest BLHelli. Bootloader survived, but BLHeli was gone. I have to connect ESC to other FC and then reflash. I wonder if it was hardware or software issue…
    Right now, apart from FPV gear, FrSky receiver, GPS mount, SmartPort inverter and final assembly GPS Racer is few steps closer to being finished. With upcoming Easter, it should be functional in April. Can't wait…

Omnibus F4 Pinout

Omnibus F4 is a new family of All-In-One (AIO) STM32F4 based flight controllers with integrated OSD (On-Screen-Display) for FPV purposes. Basically, it is Airbot F4 / Flip32 F4 with added MAX7456 and some minor tweaks.

  • OSD connected via SPI bus
  • VCP port
  • 3 UART ports, UART3 is shared with I2C
  • Hardware inverter on UART1 allows to connect S.Bus receivers
  • Dedicated PPM/S.Bus connector
  • DSMX connecter
  • PWM connector that allows to connect 4 PWM channels
  • Integrated voltage stabilizer and voltage monitoring
  • Analog current monitoring
  • Analog RSSI monitoring
  • Buzzer connector
  • Integrated 16MB Blackbox flash memory

Currently, only Betaflight and Raceflight (?) supports OSD on this board. INAV OSD support is on its way.


  • RAM pins are connected only to each other. For OSD only GND and Video IN and Video OUT lines have to be connected with camera and VTX
  • Integrated voltage stabilizer tends to get hot when powered from 4S. Do not try to power camera or VTX from it
  • Current and RSSI are NOT 5V tolerant. 3.3V max
  • S.Bus and DSMX are shared with UART1
  • To use UART1 and PPM, SBUS jumper has to be removed

Airbot Omnibus F4 Bottom What is where

Omnibus F4 can be purchased as Airbot Omnibus F4, Flip32 F4 Omnibus and “no-name” from Banggood and other Chinese shops.