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AQ6 – What Else You Will Need

FTDI / USB2Serial

The AutoQuad flight controller does not contain a USB interface. For uploading the firmware an on-board serial interface is available that can be connected to a number of FDTI or USB2Serial adapters.

We recommend the combined AutoQuad/MultiWii USB UART adapter:

You can order one at Flyduino or Viacopter

The AutoQuad MCU (STM32F407 cortex M4) ports must not be provided with voltages above 3.3v. Although some ports are 5V tolerant, best is to use an FTDI or USB2Serial where the signals are on a 3.3V level.

Below is a list of known FTDI / USB2Serial adapters that are used by the development team. You only need one of them – we recommend the cable.
Settings for the connection: 115.200, N81 and “flow control” activated
For flashing and setup you only need GND, Rx and Tx connected – flow control disabled.
Please have a look at our Wiki.

Flyduino FTDI (recommended or included)
Sparkfun FTDI basic 3.3V
Make sure to disconnect the DTR signal
No need to disable the DTR line

Some FTDI adapters will keep the DTR signal low and prevent the AutoQuad from communicating with the ground control station. In that case disconnect the DTR pin.  Please read the instructions in our Wiki

Micro SD card

The AutoQuad flight controller contains a microSD card slot.
The microSD card is vital for the AutoQuad, it is needed during the static and dynamic calibration sequence, it can store the calculated parameters (and thus a specific frame configuration), it can datalog all variables during flight and a future enhancement could be creating and storing waypoint information.

AutoQuad is very critical with the SD card performance, the firmware will offload every 10 seconds and based on the data an class 4 or 6 should be sufficient.
That is however not the case, the AQ team has tested a large number of class 4, 6 and 10 cards and only very specific class 10 cards are working.

Errors to expect on lower end class 10 cards;

  • not initializing at all
  • SDIO errors during logging in the telemetry data console
  • sequence errors during calibration logging.

The latter is very important, a sequence error should not be in the calibration file, it will disturb the final calculations.

A (very) short list of known (successfully tested) class 10 microSD cards. Some users reported problems with cards above 8GB capacity. So atm. we recommend to only use microSD cards with a size up to 8GB!

  Name/Brand Class Information
PNY Micro SDHC class 10 10 Measured speed test : 10.9MB/s writing raw data 5Mb chunks
Samsung 8GB Class 10 10 Reported as good by team members
Transcend 4 or 8GB class 10 10 Most users get good results with these
SanDisk Extreme Plus UHS-1 10 Best option atm for fast and flawless writing

A minute of data logging will record around 4MB.

Note: some users reported difficulties with their SD card not logging correctly. Some boards of the beta batch need a little “mod” by bending a latch down slightly (click on the image at right).


6 straight header pins for the FTDI/USB/Telemetry connection, and 2×2 pins for the jumpers J3 & J4 are now included with the AQ kit from Viacopter and Flyduino. If you want an angled header, or something else, you will need to provide that yourself. A 3 pin header for the I2C port is optional (not included).  Additionally, you could use one double-row angled header for the serial port and jumpers, and/or for the motor output ports.
To shorten J3 or J4 some simple computer jumpers come very handy. You could also use a short servo cable where you only use 1 wire.
For easy mounting of the board on standard 4,5×4.5cm holes some 15mm standoffs are recommended. You could also use some rubber or aluminum bolts.

A piece of Open Cell foam is needed to cover the baro/pressure sensor from light and wind. Make sure it’s not too dense so the baro still can “breathe”.


Some users reported problems when powering their receivers, servos or video equipment through the AQ FC.
That’s why we recommend using an independent power source for these units. Several shops offer cheap 5/6V UBEC with noise reduction. You can order one here.

RC Receiver

See the dedicated page for RC system options.

GPS Antenna & Shield

You will need an active GPS antenna, best are 35mm ceramic antennas by Taoglas or similar. For a better shielding of your sensors and an extra ground plane you can use a shield like this.  It can easily be mounted above the FC on standoffs in a 45x45mm pattern.  More information on this page.

You can order the AQ GPS shield at Flyduino or Viacopter

This page was created on 14-Jun-12 by menno. Last modified on 10-Jan-15 by menno.