STM32 F1, F3, F4, G4, F7 and H7 flight controllers

STM32 F1, F3, F4, G4, F7 and H7 flight controllers

Currently, almost all flight controllers we use on our multirotor FPV drones and airplanes are powered by microcontrollers from an STM32 family. When we say about flight controller families or generations, we refer to them by the family of the MCU. For example:

F1 flight controllers are no longer supported

or

You should get F7 to do it

STM32F1

Historically speaking, F1 were the first flight controller boards for MultiWii derivatives based on STM32 MCU. All the F1 boards like Naze32 or CC3D (ok, this one is from OpenPilot family) were equipped with STM32F103 chips. Currently, F1 boards are not supported by any major flight controller firmware. Reasons are simple: low speed, lack of hardware floating-point acceleration, very little RAM and Flash memory, only a couple of UARTs. They were not powerful enough and as a result, had to die.

Do not buy and if you have one, just keep it somewhere in a drawer as a souvenir of good old times. Read More

Betaflight vs EmuFlight vs INAV

Which flight controller software flies better out of the box? You know, the stock, default settings, no tuning. Just flash and fly. Betaflight, INAV or maybe EmuFlight? I decided to test it on one of my 5-inch FPV drones and compare: Betaflight vs INAV, Betaflight vs EmuFlight and EmuFlight vs INAV.

The results are divided into 2 separate videos. In the first one, I explain all the rules and present all 3 flight controller software flying the same kwad.

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The best flight controllers for INAV – 2019 Q4 edition

Believe it or not, but choosing the right flight controller for your next airplane or a drone build is quite important. Yes, I know that some of you might say that hardware does not matter and your kwad will fly as good with the latest F7 flight controller as it would fly with Naze32. It is, not true. It would fly with Naze32, but do not even try to compare modern flight controllers with more advanced filtering, inputs, outputs, and peripherals.

Best flight controllers for airplanes

Matek F722-WING

Matek F722-WING

Matek F722-WING is the second generation of a big WING flight controllers started by a famous F405-WING. Comparing to the original, F722-WING offers more input/output options, including dedicated airspeed port, switchable camera inputs and switchable power supply for FPV installation. Read More

The future of F3 board in INAV

It’s time to start saying goodbye to F3 boards in INAV. History repeats itself and after we let F1 boards go, the same fate upon F3. Why? STM32F303 does not have enough RAM to handle everything that is demanded of it: OSD, telemetry, GPS, navigation, etc. INAV already is not enabling the majority of new functions on F3 based boards!

What will happen next? Most probably, F3 boards that fail to build due to lacking memory will be removed from the official release process. The code that drives them will stay, but if anyone will want to compile INAV for them, they will have to find missing memory by himself.

So, do not expect INAV 2.4 running on Omnibus F3. On the other hand, SP Racing F3 will probably stay with us for a little longer. Lack of OSD is a huge advantage in this case.

Matek F765-WING – flight controller on steroids!

This is preproduction sample, some details of Mateksys F765-WING might change in the final version that will hit the market!

Mateksys F765-WING

Matek F765-WING on Banggood

Looks like Mateksys did it again, and the next flight controller in WING family will be one again the beefiest flight controller around! What’s new? A lot. It’s still the same format as F405-WING and F722-WING, but this time, the top plate is not only a plate. It holds 8A continuous (10A burst) BEC that you have to connect with wires to the main plate. From what I’ve been told, the step-down chip itself can hold 20A continuous, but due to limited space, the main inductor/choke limits it to 10A only. Well, only is probably not the best world 😉

Mateksys F765-WING

The brand new is also CPU. Now it is beefy STM32F765 in LQFP-100 package. Beefy because it has 2MB of flash and 512kB of RAM. And thanks to the big package, a lot of peripherals could be broken out:

  • 12 PWM outputs
  • 8 UARTs
  • 2 I2C
  • SPI
  • 6 ADC (Vbat, Current, Vbat2, Current2, RSSI, AirSpeed)
  • Micro SD
  • camera switcher
  • switchable 5V/9V output

Mateksys F765-WING

Compatible software: INAV, Betaflight and (probably) ArduPilot.

Matek F722-SE – brand new flight controller that brings STM32F7 closer to the needs of many

At the beginning of 2018 I’ve stated that Matek F722-STD is the first F7 flight controller that makes sense. Today, I have in front of me I have the first F7 flight controller that has all you need (and more) when 4-in-1 ESC is not what you are looking for.

It is Matek F722-SE!

Matek F722-SE Flight Controller

Matek F722-SE Flight Controller

Matek F722-SE Flight Controller

  • STM32F722 processor
  • MPU6000 and ICM20602 gyro/acc – user selectable to match the needs. Personally, I’m not the biggest fan of dual gyro design. From my perspective, MPU6000 is enough for everyone. Really!
  • OSD compatible with INAV and Betaflight
  • BMP280 barometer
  • 5 hardware serial ports
  • possible 1 software serial
  • 8 outputs
  • I2C bus

This is the standard data. Nothing super fancy at a first glance. Until you go into the details:

  • PDB with a current meter is integrated into the design
  • you can connect 2 separate FPV cameras and select the one that will be connected to OSD and VTX with your radio without any additional hardware. Super option for fixed wing flyers
  • power VTX on/off from your radio as well (I really will have to test that soon)
  • TX6 is conveniently positioned at every corner for ESC telemetry setup
  • F7 means that you can connect anything you want to any serial port you want. F7 series have integrated serial inverters, so SBUS and SmartPort is no longer a problem

I’m super eager to put this baby on one of my racing quads

Matek F722-SE is coming soon!

Mamba F405 and F40 40A 3-6S 4-in-1 ESC combo hands on

I have to honestly admit, up to the beginning of 2018 summer I was rather against 4-in-1 ESCs and flight controllers combos. The reason was quite simple: 4-in-1 were a rather new thing, had a tendency to burn without a reason and were quite expensive. Pretty much a normal state of a new technology. In comparison, FC + PDB + 4 separate ESC had more flexibility, were cheaper to replace when something puffed the magic smoke and seemed to be a reasonable choice when few extra grams of weight was not a problem. Lately, things started to change…
4-in-1 ESCs are no longer a new thing, manufacturers learned their lessons and prices went down! And that means you can get a decent quality flight controller and 4-in-1 ESC for less than $50. That's cheaper than 4 ESCs! C'mon, things ARE happening.

Today let's take a look at the example of a new age FC + 4-in-1 combos: Mamba F4 Power Tower.

Mamba F405 and F40 4in1 ESC combo

Mamba F405 and F40 4in1 ESC combo

Mamba F405 and F40 4in1 ESC combo

What comes inside the package?

  1. Mamba F405 flight controller
  2. Mamba F40 4in1 ESC

Mamba F405 flight controller

Mamba F405 and F40 4in1 ESC combo

Mamba F405 and F40 4in1 ESC combo

Mamba F405 comes preflashed with Betaflight 3.3 and uses target FuryF4 OSD (FY4O). It comes in standard 30,5×30,5mm hole spacing.

  • STM32 F405 processor
  • SPI connected MPY6000 gyro
  • 3 hardware serial ports: UART1, UART3, and UART6
  • LED support
  • built-in OSD
  • built-in 16MB flash memory for blackbox logs
  • I2C pads

Mamba F40 4in1 ESC

Mamba F405 and F40 4in1 ESC combo

Mamba F405 and F40 4in1 ESC combo

  • 40A constant, 50A peak current
  • DSHOT support
  • uses QN3109 MOSFETs
  • current sensor

Pros and cons

Some pros and cons after taking a "static" look at Mamba F405 and F40 4in1 ESC

Pros:

  • pretty good quality PCB, I would even say surprisingly good for a price
  • FC comes with rubber grommets for vibration damping
  • side mounted DFU button instead of flat buttons or just pads on some lower quality boards
  • c'mon! $45!

Cons:

  • FC can be used only with 4in1 ESC, no separate soldering pads for ESCs
  • There are many versions of QN3109 MOSFETs, and depending which PDF you take a look at, 40A rating is either overrated or underrated… hmm…
  • location of pads for motors on the 4in1 is problematic. It collides with mounting standoffs. Careful soldering required!

Overall verdict? So far, positively surprised! Really, this thing goes to one of my mini quads immediately!

Matek F722-STD not booting without battery and how to fix it

What to do when Matek F722-STD flight controller is not booting without connected battery and connection from Configurator is not working? Simple, power GPS and magnetometer from a different pad.

All 5V pads are powered only when external power is supplied to the flight controller. Not when power is applied via USB cable. If you connected GPS and magnetometer to 5V pad, it will not work and screw I2C bus up. To solve this problem, connect GPS to 4V5 pad instead!