How to flash the Mini OSD with uOSD

How to flash the Mini OSD/E-OSD with uOSD?

I disclaim all responsibility if you break or damage your equipment when following this tutorial. You’ll follow this tutorial at your own risks

Hi everyone,

Since there is no complete outline I decided to make a tutorial on how to flash the Mini OSD with uOSD (Thanks again to alexmx from RC groups who created this awesome firmware!)

Here is what you need :
– 1x USB AVR Programmer
– 1x Mini OSD system w/GPS module
– 2x pairs of Servo plugs
– 1x 10 cm servo wire
Optional: Hot glue

I. Preparing the Mini OSD :

Before getting started, we need to prepare the OSD to be able to flash it:

Il faut commencer par retirer la gaine thermo transparente de l'OSD.

First, you need to remove the transparent shrink tube that protects the OSD.

Retirer l'étiquette de l'OSD

Then take off the tag.

Voici le détail des pins

Here is what you get | You also have the pin details for flashing

Pin details for flashing the E-OSD | Thanks to PeterVRC (RCgroups) for the picture.

Pin details for flashing the E-OSD | Thanks to PeterVRC (RCgroups) for the picture.

Now, you’re going to prepare the 10 pins flat ribbon to connect the AVR programmer to the mini OSD:

Le détail des 10 pins venant du programmateur USB AVR

10 pins connection from AVR programmer

You’ll notice that we don’t use pins 3, 4, 6 and 8. Pin 3 is a not used signal and others are ground.

Then will have to connect the AVR’s ribbon to the OSD with the same signals (that is MOSI on the OSD connected to MOSI on the AVR…etc). Like me, you can use servo plugs to be able to connect/disconnect the OSD to you computer.

Because the purpose of this is not only to flash but also configure it as you prefer.

Here is the result with servo plugs:

Mini OSD connecté à l'USB AVR

Mini OSD connected to the AVR

OSD connected to AVR

Here is another way to do it with a 2mm single row female pin header: (By SeByDocKy from
Seby Docky 1
Seby Docky 2

With the ribbon to be connected to the AVR programmer

With the ribbon to be connected to the AVR programmer

II. Flashing the Mini OSD :

=>Before starting this part, you must install your USB AVR programmer’s driver
=>No need to supply the Mini OSD, the AVR will take care of it

Download this document. Then extract the folder where you want. For me, it’s on the desktop.

Connect the Mini OSD to the AVR and the AVR to your computer.

Open “u-osd2-master” folder, then open “bin” and double-click onto “uSetup.exe”. (If a security window shows up, click “Yes”)
This software will show up :
uOSD home

After having checked that your Mini OSD is connected to your AVR, which is connected to your computer.

Go to the menu => OSD => Update firmware

uOSD Firmware 1

A confirmation window will show up, click “Yes”:

uOSD How to

In the file explorer, open the folder “u-master-osd” => “bin” => “data” and double click onto “u-osd.hex” which is uOSD’s firmware.

uOSD Firmware 3

Two windows command line will show up. When it’s done, the uOSD log should display “firmware successfully updated”

Fabulous, your Mini OSD is now flashed with uOSD!

You can now configure what your OSD will display in the Panel’s tab.
And configure the OSD in the main tab.
Then go to “uOSD” => “OSD” => “Write to OSD”

Whether you have the old or new GPS, the baud rate is 4800 bps that you must set in uOSD’s software to get it to work.

To make sure the GPS works correctly (and that the baud rate is correct), when everything is connected, the bar next to the satellite dish should be rotating. That means the GPS is acquiring satellites. If not, the baud rate is incorrect or the GPS isn’t connected properly.

I would also recommend you to select “With button” in the “Set home” section.

You’ll also need to adjust the battery’s value or the RSSI’s.

Mini OSD potentiometers

For the battery’s value, it’s recommended to have a high precision voltmeter to measure your battery’s voltage and then adjust it according to the battery’s potentiometer until the two values match.
Here is what you get once your Mini OSD is flashed :

uOSD in flight

III. Finishing touches :

To reinforce the fragile solderings and have something more “Plug & Play”, I would highly recommend you to add hot glue:

Colle chaude pour coller les deux connecteurs sur l'OSD - Colle chaude aussi les connecteurs servos pour être plus simples à brancher.

Hot glue to glue the servo plugs to the OSD – Also on males servo plugs to be easier to plug.

Le résultat fini - Peu ragoûtant mais parfaitement fonctionnel!

The finished product – Not pretty but perfectly working!

For those who use Immersion RC or Fatshark equipment, here is my connection diagram :

Mini OSD Fatshark IRC Diagram

IMG_3363 redi

And here my Swift II ready to fly FPV with the Mini OSD :

Swift II FPV

In flight video 😉

Feel free to ask questions in the comments section 😉

Posted in Tutorials.


  1. Pingback: Comment flasher le Mini OSD/E-OSD avec uOSD

  2. Very impressed with the detail and the close up pictures of this setup.
    Great work and I will return for more reviewing and information. Keep up the great work.

    My project involves building from scratch, is a quad-copter for my first time. I have much to learn. -Arizona

  3. Thank you for the great guide. Just flashed mine and got it to work. Haven’t done a real world test yet since the quad I’m gonna install it on is still under work.

    Can you clarify some of the setting in uOSD setup?
    What do these do? “Min fix count” and “Min Fix Sats” Are 10 and 4 ok? What is the minimum sats that you need for a good lock?

    Also the GPS module keeps blinking green. Does that mean it’s acuiring sats? Will it give a solid green once it has a good GPS fix?

    • Hi Sami,
      You’re welcome :)
      “Min fix sats” corresponds to the minimum number of satellites you need for the OSD to be ready to fly. I don’t know about the “Min fix count”, mine is set to 10 and it works 😉
      You need at least 4 satellites to have a correct position. Then more is better 😉
      I couldn’t have a hand on the new GPS (since the only one I got never worked ><) so I cannot tell you anything about it for the moment =S You might have flown it already but the baud rate for new GPS might be 9600 instead of 4800 😉

      • Thanks for the info. Got my quad built, but haven’t still hooked up the OSD. Trying to tune my FC first.
        The top right corner on the OSD showed “6”, which I gather means it has 6 sat fixes, so it should have a lock, but the green light was still blinking and the GPS was acting up. Altitude kept changing alot and distance from home wasn’t near correct.

        I’ll keep testing if I get it to work. All I really need is a battery indicator, but if I get a working GPS / OSD for 20$ that would be awesome 😉

        • Sounds good.
          I still fly with the old GPS (no led) and I usually take off when I have at least 4 satellites in the upper right corner.
          You should be able get it to work, mine works like a charm ^^

          • Hi,

            Did my first test flight with the OSD today. Got good lock with 9 sats, but the GPS info isn’t right. Home position and altitude is jumping around like crazy. It should work since I get a lock, but don’t know if it’s some setting that I need to change.

            Any suggestions.


  4. Hi,
    I have problem in setup it displays firmware updated and data wrote to osd but it doesn’t displays OSD. I checked the unit with orginal firmware and it was ok, and now when i push the button led on osd turns off any sugestions?

    • Hi Aleksander,
      That’s awkward. In case of problem during the flashing process, the software should have told you that a problem occured.
      Does it work when hit “Read from OSD” in uOSD software?

  5. EurnyRC,
    Thank you very much for this tutorial. I also like your other pages. :)
    Happy flying for 2015.

    Merci pour ce tutoriel. Vos pages sont tres interessent.

    Bon vols pour 2015.

  6. Eurny:

    Your attention to detail, photography, and labeling is outstanding.
    I will be using your instructions to setup my own mini OSD and FPV gear on my Bixler, mini Skywalker, PKZ P-28, and other planes soon.
    The music for your video is well chosen. It is pleasant, relaxing, and not distracting from the flight.
    This DIY video and instruction stands as a great example for others who will undoubtably follow your lead in sharing this hobby with others.


  7. Thanks for your documentation of this – it was very helpful and easy to follow for setting mine up!

  8. Hi. I am trying to flash HK miniosd with avrtinyisp but with no success.
    I understand that it is due to the fact that it is 88pa. Do you know the solution?

    • Hi Igor,
      Best way would be to buy a cheap AVR USB like the one I have. You can get one from ebay for $5 and it always be useful in the future 😉

  9. I done the mod. Very impressed. It`s work perfectly. It take me about 15 minutes to solder the wire, flash and rewrite my E-OSD.
    I use it on my 250 Quad racer to monitor my lipo, it`s tiny and fit perfectly everywhere.

    Thank you for the tutorial.

  10. Great tutorial page. Thank you so much for sharing your knowledge.

    One question- Is your setup using the Mini OSD still working great and no problem encountered at all?

    The reason I asked is that I just noticed now that the Mini OSD does not have any “video in” to mixed the camera signal before it send the video to the transmitter. It actually just directly tap into the video signal wire from the camera to the transmitter. This looks like the video output of both the camera and the OSD are partly feeding to each other’s output pin and I was just wondering if it could cause any damage to any of the component.

    I would very much like to know if the same setup is still working as of today and/or if you have made any other modifications to it lately.

    Thank you again.

    • Hi Rico,

      Yep, mine is still working well! The only modification I have done is adding a capacitor in parallel on the power input. With the motor/ESC setup I was using, the OSD was getting crazy at full throttle. Since the capacitor, no more problems 😉

      Considering your “issue”, it’s not big deal. You have only one video pin used since the OSD adds its information to the video signal in parallel. It was also a little bit awkward to me since OSD usually have a “Video in” and “Video Out” pins. But, see the bright side here. If at some points the OSD stops working, you can still fly back and land 😉

  11. Thank you for this very detailed tutorial/guide.
    The custom firmware looks much better (professional) than the stock one
    I’m planning to use the miniOSD together with my X380 Quad.

  12. Does the GPS module have to be connected to the OSD when flashing the OSD? I keep getting an error message whenever I try to flash the new firmware.

  13. One friend bought from Hobbyking the Excellence OSD w GPS. Unfortunately he recognized after receiving the part, that it has a useless OSD surface. Because it is for him to difficult to modify the OSD software, he asked me for help. Looking into internet I find your homepage and thanks to your very detailed tutorial/guide I was able (in spite of my age > 70) to modify the software to U-OSD surface. Instead a USBasp interface I used my RS232- ISP Interface , and modified in window “programmer type” the USBasp to “ponyser”. With this change I started to download all to the OSD board without any problem.
    Thank you for your perfect discription and also thank you to Alex for his excellent software.

    with regards Joe

    • Yes, it’s not going to be easy but you can solder directly on the ATMEL pin. You need to download the ATMEL component datasheet to identify which pin corresponds to MOSI and you’re good!

    • I had 2 pads come off as well. What I did was carefully scrape off the green resin from the track leading to the pad, and soldered fine wire to the track very carefully.
      Tested my connection further up the track, then hot glue over to protect it as the tracks are very fragile as well. Soldered to the new wires leading to servo plugs as in this tutorial, then hot glue everywhere to protect it all.
      I’ll be more careful on the next one.

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