Phantom 3 Pro gimbal falls asleep after drone is turned on / no signal

[Infinite_parts]

Hi folks,
Another issue with P3P. Not sure what really happened but now P3P gimbal is falling asleep after drone is turned on. It dances that starting loop then green light blinks few times and camera goes down like falling asleep. I know that GL300C RC is recently upgraded. Yesterday this P3P drone was flying and all was good but today it shows no signal and no upgrade works as well.

Now I tried to make an FW upgrade to P3X_FW_V01.11.0020 (gimbal does nothing if turned on normally) Therefore I tried to hold the reset button while turning on the drone with formatted card (only FW on it).

At the beginning looked like it is trying to upgrade but now more than 30 minutes has passed and camera keeps sleeping (gimbal does not get up in center position).

NOTE: Interesting was that - I just realised I had ND filter on it. Gimbal was falling asleep (down) when filter was on. Now I took it off and retarted the drone, but now instead of dropping camera down it is going into lean position (like on one side a bit). Still no signal message appears on DJI GO app.

Any suggestions, steps to take to get rid of this incident? @quaddamage any suggestions without flashing?
Isn't this the Gimbal OVERLOAD case when I need to adjust side arm motor position?

Thanks in advance anyone.
Cheers

 

[quaddamage]

If an update failed, you should always look at hidden log:
No signal after crash or firmware update failure.

In the log, you will find info whether all modules can respond to query for version sent by the camera. If any of the modules is "not found" - then you know where the issue is.

If nothing suspicious is in the log file:

Gimbal issues are hard to diagnose, because the DAT log does not store packets from gimbal. Mefistotelis from GitHub suggested recording communication between OFDM Board and ESC Center Board, but I had no time to get into this yet. It is also possible that the packets from gimbal are stored in the TXT log on mobile device - I never looked into these logs in detail.

Anyway, without any known way to ask the Gimbal Controller for its status or error code, the best solution is to blindly replace parts with known good ones, until it starts working. By parts I mean: Flat Film Wire, Gimbal Driver Roll, Gimbal Driver Pitch and Camera Sensor Board.

The board names I'm using are from here:
o-gs/dji-firmware-tools

 

[Infinite_parts]

If an update failed, you should always look at hidden log:

Thing is that gimbal does nothing with the SD card at all - I have formatted SD card, with FW on it (also tried with DEBUG file on it) but when I turn on Drone, it does nothing with that card and there is no hidden LOG file after I take out the SD card..

 

[quaddamage]

when I turn on Drone, it does nothing with that card and there is no hidden LOG file after I take out the SD card..

Oh, so Ambarella is not booting? Does the LED near SD-card slot blink?

We don't know how to re-flash Ambarella. But we do have some clues:
o-gs/dji-firmware-tools

If you want to find a way yourself, start by tapping to the interface mentioned in "Debug serial interface U0" chapter. Check whether you can see any text there while the device is turning on.
To turn it on without the drone, you can either supply it with 12V to the ribbon which connects it to ESC Center board, or 5V to the test pad marked "5V". Note that is requires quite a bit of power - standard 500mA USB port is not enough.

You should also check the Ambarella A7 spec mentioned on the wiki - usually new products are evolution of older ones, so it's possible the methods from there work on A9 as well.
(we don't have A9 specification document).

 

[Infinite_parts]

Oh, so Ambarella is not booting? Does the LED near SD-card slot blink?

When you turn on camera, it makes warm up dance, then LED lights are blinking. After few seconds and dome D D D sound (it seems it will start updating) but nothing happens, camera drops head to floor and nothing happens anymore.

I have also tried updating this way - pressing reset button on OFDM and then turning on Drone. then it seems something more happens but camera keeps dropped head into floor. sometimes green light blinks like three sets in the row and then fan turns on (during this time red and green led jumping), after that fan turns off again and process repeats in a while - green flashing, then green and red switching, then again nothing - no log file stored anyway.

 

[quaddamage]

Try tapping to the serial interface, as I proposed above.

It is possible that gimbal issue (going limp after dance) and camera issue (no logs on sd-card) are two separate issues.

 

[Infinite_parts]

[QUOTE="We don't know how to re-flash Ambarella. But we do have some clues:
o-gs/dji-firmware-tools

If you want to find a way yourself, start by tapping to the interface mentioned in "Debug serial interface U0" chapter. Check whether you can see any text there while the device is turning on.
To turn it on without the drone, you can either supply it with 12V to the ribbon which connects it to ESC Center board, or 5V to the test pad marked "5V". Note that is requires quite a bit of power - standard 500mA USB port is not enough.[/QUOTE]

Did not get really how can I read that text, where should it appear?
Can you specify the procedure of that Debug serial interface U0 - I understand I need to give 5V power to that 5V pin on the board but how should I read it?

Thanks

 

[quaddamage]

Did not get really how can I read that text, where should it appear?

You have USB-to-TTL? Solder its GND, RX and TX to test pads on the gimbal board.
Also solder cables to 5V and GND test pads, so that you can power it when disconnected from the rest of the drone (if the board is not disconnected, don't do that).

Start PuTTY on your PC. Select "serial" connection, type the name of your USB-to-TTL port, set serial transmission speed to 115200, no parity, 8 data bits, 1 stop bit.
Click "Open". Console screen will pop up. Now turn on power to your board. You should see text. If not - check if everything works when you connect it to a working board.

You can use the same method to access most serial interfaces within the drone. I only accessed DaVinci, never tried Ambarella or others.

 

[Infinite_parts]

Should I tap USB-TTL pin to 5V pad if I connect it with ESC Central board via grey 8 wire ribbon cable? Or is it better to just solder wire to 5V and connect with DC power supply rather than 5V cable to USB-TTL ?

I just tried like:
TX, RX, GND from USB-TTL to service pads + I connected it with ESC ribbon cable for power and when I run PuTTY I receive not quite text not quite symbols. I get some mixture of information which seems to look crippled.

Cheers

 

[Infinite_parts]

This is how it looks like with settings I have now mentioned above.
Cheers

 

[quaddamage]

Should I tap USB-TTL pin to 5V pad if I connect it with ESC Central board via grey 8 wire ribbon cable?

No. Use ribbon or 5V pad, not both.

Or is it better to just solder wire to 5V and connect with DC power supply rather than 5V cable to USB-TTL ?

Your USB power may not have the amperage you need. It is safer to connect it to voltage source with higher power.

I get some mixture of information which seems to look crippled.

If you receive garbage, then it means the board is sending something, your terminal is just not decoding it correctly. Make sure you configured PuTTY as I described.

EDIT: I can see at bottom of your screenshot that your settings are bad.

 

[Infinite_parts]

EDIT: I can see at bottom of your screenshot that your settings are bad.

Done everything as you said:
New session - Serial - Serial line COMname - Speed - 115200 - Data bits 8 - Stop bits 1 - Parity None
Cannot understand what have I done wrong..

TX to RX
RX to TX
GND to GND
Power either 5V from DC bench supply or via Ribbon cable from ESC Center board.

Anything else?
Cheers

 

[quaddamage]

Cannot understand what have I done wrong..

Look at the speed visible at bottom of the screenshot.

 

[Infinite_parts]

Look at the speed visible at bottom of the screenshot.

It does the same with 115200 speed as well..

 

[quaddamage]

Well, all I can tell you is that: since you see the "bushes", the cables are correctly soldered to the board, and processor on the board (ie. Ambarella if you connected to that processor) is sending something.

There are ones and zeroes in the cable, now it is up to you to receive that information so that is is shown correctly as text.

Maybe it's your USB-to-TTL converter. Maybe your parameters are wrong. Maybe even the wiki is mistaken and you should use different speed.

 

[Infinite_parts]

Ok guys, maybe you can assist on this one, maybe that will solve my issue..?

Here you can see my FW versions for app, RC and Aircraft.. is there any possible normal way I can get rid of these latest updates and jump back to into some previous ones. I just want to see if the issue with no image will stay the same.
Funny part is that app shows gimbal is disconnected but when I move camera with RC left roll button it moves up and down (different gimbal but with latest soft on it) hat one does not react to bin files on SD either.
Any help here?
Cheers

 

[quaddamage]

is there any possible normal way I can get rid of these latest updates and jump back to into some previous ones

Ok, as I understand we're talking about a different drone now.

Here's the best guide for downgrading:
Downgrading firmware on P3P from 1.10.9 to 1.7.6

If you see no image, you should follow this:
Fix no video feed / black screen / no image transmission / no FPV on Ph3 Pro

 

[Meta4]

Thing is that gimbal does nothing with the SD card at all - I have formatted SD card, with FW on it (also tried with DEBUG file on it) but when I turn on Drone, it does nothing with that card and there is no hidden LOG file after I take out the SD card..

Have you tried it with a different card or no card at all?
The dead gimbal after boot up can be because the camera just doesn't like something about that particular card.

 

[Infinite_parts]

Have you tried it with a different card or no card at all?
The dead gimbal after boot up can be because the camera just doesn't like something about that particular card.

Yes, have tried two cards which I know previously worked. Tomorrow can try another one. Have not much of those cards though. If with no card, camera goes limp as well.

 

[Meta4]

If with no card, camera goes limp as well.

That's something else then