Hi all !

I need help about my MinimOSD freshly unpacked.

I've triple checked the cabling and I don't know why I've just a black image on my screen.
There is a suspicious comportement when I power on the system. I explain how it happens:
1. Connect correctly the Vin/Vout/RX/BLK between APM, MinimOSD and video transmitter 
2. Power on the APM 
3. Connect the battery balance connector 12V to the MinimOSD  

At point 2, the ST led (orange) blink and the D PWR (red) led power on and still.  
When I do the point 3, the ST led shut off and the A PWR led power on and still. 
After that, I just have a black screen... It's weird because the system worked at least once!  
The firmware is up to date and I use a XBee but I've not connected the TX port on the minimOSD.

What's wrong ? Someone can help me ?

Thanks in advance ;-)


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I did a bit of testing and can confirm that using a V0.1 minimOSD powered by the APM works. I haven't fried this OSD (at least not yet), but have been careful to power up the APM before the video system. I have added solder blobs to the back of the board to tie the analog and digital power rails, and have removed the V+ pins from the pin headers that connect to the video in/out connectors.

I'm not sure why this is, however, but I have to cycle power to the APM after the minimOSD boots up. Otherwise, I just get the video passed through with no OSD at all. Can anyone comment on why this might be or other workarounds?

I'll keep testing with this miniOSD and hope I don't fry it. I hope this hardware flaw is repaired so the minimOSD firmware can continue to improve.

I think you have a PAL camera.

If Minimosd does not see any video when it boots, than it defaults to NTSC.

If it is the case, you have 2 choices.


Simple way is to lock Minimosd to PAL only.

In Arducam_Max7456.cpp

search for:

else setMode(0);

than change setMode(0); to setMode(1);


You can make it default to PAL and still have the possibility to use a NTSC cam:

Go to the same place:

else setMode(1);

tahan add this after #endif

if ((B00000010 & osdstat_r) < 1){

So your code looks like this:

if ((B00000001 & osdstat_r) == 1){
else if((B00000010 & osdstat_r) == 1){
#ifdef MinimOSD
else if (digitalRead(3) == 1){
if ((B00000010 & osdstat_r) < 1){

else setMode(0);

Hope it helps


My 3rd MinimOSD is supposed to be on its way after blackscreening (fried) the first two. 3DR can't tell me why this is happening and went as far as telling me I can power the APM (digital +5V Mavlink) and the video side of the OSD (+12V analog) from the same battery. This is the configuration that destroyed the first two. This time I am going to try tying the analog and video together like you did. Are you just using the video in/out pins or do you also have to use ground on the video side?

I, like you, am nervous about ruining another one not knowing what’s causing it. It seems like using two separate batteries was never a problem.

Hmmmm.....  I have read about this problem. so i decided to use the 5v fom mavlink.

On the video connectors, i do not use the middle pin. only video and ground.

I do not have 2 battery on board anyways. Using one for all.

It works great for me. :)

Hope you will be happy with your 3rd MinimOsd! ;)

About the power issue: the reason why for some people different solutions work, could this be caused due to the revision of the hardware that (as I read somewhere) involved a change of the voltage regulator?

Just a thought.. I'm planning to use separate batteries but I wonder why using the same would cause problems. Maybe a diode missing somewhere?

Hi Andre. I fried the latest revision hardware (with the switching regulator), and have switched back to the v0.1 hardware. I've removed the centre pin from the in/out headers and so far so good...

Thanks, Gábor, for your code change. I had a solder blob on the back of the board to default to PAL, but it wasn't working, it seems. Works fine now. No extra reboots required.

I suppose I fried mine today.. I did not find this thread until too late.  I just blindly followed the very nice wiki on how to install it.  I am not happy..

Anyway, how can I tell its fried, other than no video?  It still seems to accept uploads when connected to computer in the config program.

Man, this makes me ticked...

I know how you feel, Mack.  I sure felt ticked by a reassuring wiki when I killed mine.  Mine still accepts uploads too.  I think that just the analog side is fried.  I wish someone would chime in on what, exactly, gets fried, or maybe perform an autopsy.  Maybe we can swap out the OSD chip (with some careful smd soldering) and bring the board back to life? 

You have all the symptoms of a 'black screened/fried" OSD. I just received my third one today. I am very nervous experimenting with it now! Let me ask you this. Were you powering the digital and analog side separatly? APM powering the digital via the Mavlink+5V and the analog +12V? Were you using the same battery for both? This is what I did and destroyed the first two. The computer will still talk to the digital side but the video side is toast. When I used two batteries, one for the APM and one for the video, all was fine.

Someone said they replaced the video chip with no luck. Even 3DR can't tell me what is happening.

Sorry if I caused any confusion, my minmOSD which I have been running from a single battery is a v0.1 board, which sounds like it doesn't have the issue the later boards do.

Don't you have any kind of interferences on your video like horizontal lines, servos,etc.? Are you using some kind of filter?, I'm using one battery powering both sides but the minim becomes very hot, I don't like this anyway :(

Hi Cala.  If your MinimOSD is getting hot, I suspect you are using the V0.1 hardware with the linear regulator.  You will probably soon fry it if you're not careful.  As others have said:

* Remove the +12V pins from the Vin and Vout headers. 

* Put solder blobs on the board so it is powered from the APM +5V.

* Make sure the digital and analogue grounds are tied together (a solder blob on the back of the board).  A difference between these, such as is transient when connecting your motor, is the main cause of death, AFAIK. 

* Yes, you may get interference from the motors/servos.  You may need to add capacitors or a good L/C filter to smooth these out and you probably won't be able to 100% eliminate them.  Better noise than a dead MinimOSD, I always say!

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