P3P Motor Grinding

[Uncle Stumpy]

That's the pitch motor that has come loose. Its hold by 3 tiny screws. You need to disassemble it to fix it.

Know of any videos to show how its done?

 

[Pegasus Robin]

Know of any videos to show how its done?

I used this one

very good step by step instructions

 

[Uncle Stumpy]

I used this one

very good step by step instructions

Thank you!!!

 

[Pegasus Robin]

Ok, so I found an old firmware P3X_FW_V01.01.1003 put it onto the SD card as normal and turned on the quad. Same thing. It attempted to load the firmware, the light went out and then started flashing green again. I turned the quad off, looked at the log file and nothing. Is there anything I'm doing wrong?

 

[Pegasus Robin]

Update. I'm now getting a red flashing light on the gimbal and it won't take any firmware i try to load onto it with the SD card

 

[quaddamage]

Ok, so I found an old firmware P3X_FW_V01.01.1003 put it onto the SD card as normal and turned on the quad. Same thing. It attempted to load the firmware, the light went out and then started flashing green again. I turned the quad off, looked at the log file and nothing.

If Ambarella isn't able to write log, then the Ambarella firmware must be damaged. This will be hard to fix - not because the procedure would be difficult, but because we don't know the procedure.

As far as I know, we don't even have datasheet of the Ambarella A9 chip.

 

[Pegasus Robin]

Update. I'm now getting a red flashing light on the gimbal and it won't take any firmware i try to load onto it with the SD card

Second update, there's now no light at all and won't take latest firmware

 

[Pegasus Robin]

If Ambarella isn't able to write log, then the Ambarella firmware must be damaged. This will be hard to fix - not because the procedure would be difficult, but because we don't know the procedure.

As far as I know, we don't even have datasheet of the Ambarella A9 chip.

Oh no

 

[Pegasus Robin]

@quaddamage Hi, I might just have something for you in the way of logs from the Go app. Here's the .txt file. If you have the time, please could you take a look at it?

 

[quaddamage]

@quaddamage Hi, I might just have something for you in the way of logs from the Go app. Here's the .txt file.

It is interesting, thank you; I didn't know Dji Go stores update logs for the RC. This might be useful is someone damages RC during update, or if the RC doesn't work properly, but still accepts updates. Where are the logs stored in the directory tree?

Regarding your case - fixing Ambarella on gimbal board - it would be hard to go anywhere without soldering; but if you can solder, then we could do some tests:
- try to tap into Ambarella UART console, check whether it prints anything
- try to change boot mode in Ambarella to USB Boot (we'd still need USB boot image)
also, we could try gather more info:
- try to search the net for Ambarella A9 datasheet (aka "System hardware" documentation)
- try to search code repositories (github?) for Ambarella A9 SDK (Software Development Kit)
- study the "Ambarella A7L System Hardware" document, which is available online - hopefully many solutions from A7 still exist in A9
- study the existing knowledge on the module:
Firmware m0100 · mefistotelis/phantom-firmware-tools Wiki · GitHub

 

[Pegasus Robin]

It is interesting, thank you; I didn't know Dji Go stores update logs for the RC. This might be useful is someone damages RC during update, or if the RC doesn't work properly, but still accepts updates. Where are the logs stored in the directory tree?

Regarding your case - fixing Ambarella on gimbal board - it would be hard to go anywhere without soldering; but if you can solder, then we could do some tests:
- try to tap into Ambarella UART console, check whether it prints anything
- try to change boot mode in Ambarella to USB Boot (we'd still need USB boot image)
also, we could try gather more info:
- try to search the net for Ambarella A9 datasheet (aka "System hardware" documentation)
- try to search code repositories (github?) for Ambarella A9 SDK (Software Development Kit)
- study the "Ambarella A7L System Hardware" document, which is available online - hopefully many solutions from A7 still exist in A9
- study the existing knowledge on the module:
Firmware m0100 · mefistotelis/phantom-firmware-tools Wiki · GitHub

Hi again. Thanks so much for your help. We took the gimbal apart and went over the connections again. Powered on the drone and we have a partial success. I now have image, control. The problem however is I now have a camera error code 01 and can’t format the card , there’s no green gimbal light and it’s still not taking the firmware. Everywhere I’ve read says the gimbal main board is fried. Is this true? Is there really nothing more I can do?

 

[Wrecked]

Could you check the cable from the gimbal to the ofdm module again. Is it seated properly in both connectors?

Im also a bit concerend about the fact you failed to properly install the ribbon cable twice. Is there a chance you damaged it?

 

[Pegasus Robin]

Could you check the cable from the gimbal to the ofdm module again. Is it seated properly in both connectors?

Im also a bit concerend about the fact you failed to properly install the ribbon cable twice. Is there a chance you damaged it?

I took it to a friend of mine who’s an electrical engineer as I had a feeling I might have been a bit clumsy.
He made sure everything was connected properly and that’s when it started to work bar the camera error code.
Could it well be that I’ve damaged the ribbon cable?

 

[Wrecked]

Maybe. Could also be a firmware issue I guess.

You can try to disconnect the ribbon by unplugging the 2 connectors on the gimbal topboard. Then hook it up to the drone and see if the error persists.

Pitch and roll errors are expected, but if you get no error 01, its probably the ribbon causing the error.

 

[Pegasus Robin]

Maybe. Could also be a firmware issue I guess.

You can try to disconnect the ribbon by unplugging the 2 connectors on the gimbal topboard. Then hook it up to the drone and see if the error persists.

Pitch and roll errors are expected, but if you get no error 01, its probably the ribbon causing the error.

As the card reader isn’t reading the SD card to update the firmware, is there any other way to upload the firmware other than with the SD card reader?

Thanks again for all your help

 

[quaddamage]

As the card reader isn’t reading the SD card to update the firmware, is there any other way to upload the firmware other than with the SD card reader?

This is just repeating what I already written...
There are two hypothetical ways:
1. Tap to the serial interface of Ambarella; if it works at least partially, then it might be possible to transfer an update over serial
2. USB boot - find (or build from SDK) a USB image which would allow to boot Ambarella from USB stick/card reader; find a service pad which shorted either to "0" or "1" will cause the chip to enter "USB boot" mode. Boot the chip from USB and then reflash.

 

[Pegasus Robin]

This is just repeating what I already written...
There are two hypothetical ways:
1. Tap to the serial interface of Ambarella; if it works at least partially, then it might be possible to transfer an update over serial
2. USB boot - find (or build from SDK) a USB image which would allow to boot Ambarella from USB stick/card reader; find a service pad which shorted either to "0" or "1" will cause the chip to enter "USB boot" mode. Boot the chip from USB and then reflash.

Cool man. Thanks. I’m just trying to get my head round it, thankfully my friend does this kind of thing for a living so I’ll pass the information to him.
Can’t thank you all enough for sticking through this with me

 

[Pegasus Robin]

This is just repeating what I already written...
There are two hypothetical ways:
1. Tap to the serial interface of Ambarella; if it works at least partially, then it might be possible to transfer an update over serial
2. USB boot - find (or build from SDK) a USB image which would allow to boot Ambarella from USB stick/card reader; find a service pad which shorted either to "0" or "1" will cause the chip to enter "USB boot" mode. Boot the chip from USB and then reflash.

One thing I did find out last night was when we looked in the Go app for the firmware version of the quad it was reading 1.01 it must have taken the old firmware I downloaded somehow. Thing is, would you recommend flashing an old firmware version to the gimbal main board to match the aircraft firmware version and then update both to the latest or flash the latest and then update if it manages to reboot the board?

 

[quaddamage]

One thing I did find out last night was when we looked in the Go app for the firmware version of the quad it was reading 1.01 it must have taken the old firmware I downloaded somehow.

Well this is really strange. I doubt this is true - it's not that easy to downgrade.
Anyway, I would go with the version you had before the issue has started.

 

[Pegasus Robin]

Well this is really strange. I doubt this is true - it's not that easy to downgrade.
Anyway, I would go with the version you had before the issue has started.

Cool [emoji1303]