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Keeping .DATs on the Mavic Pro accessible

BudWalker

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Many pilots running FW 01.03.0900 thru FW 01.04.0300 have the problem that .DATs aren't accessible. The first flights on a new Mavic Pro are accessible via DJI Assistant 2. But, then after 10 to 20 flights any new flights stop appearing. I've discovered a way around this problem that some pilots may want to try. I'm hoping that this thread will help refine the methodology.

EDIT: DJI has fixed this problem with FW 01.04.0400. It's not necessary to use this procedure if you are running FW 01.04.0400 or later.

There is no guarantee that using this methodology won't adversely affect your Mavic Pro. I've been using this method for a couple of months now without any any problems - my Mavic Pro hasn't been bricked. If you run into problems, such as a bricked Mavic Pro, I'm really sorry and hope you can fix your Mavic Pro.

As I understand it .DATs get recorded on the internal SD card until it runs out of space. After that .DATs get recorded on flash memory making them effectively non-existent to most people. (I think there is a way of retrieving those .DATs but it requires a rooted Mavic and some advanced knowledge.) The trick is to periodically delete files on the SD card so that it is kept close to empty. So far, all of my new flights get recorded on the SD card where I can get them. I've been doing this for a month or so and it has worked every time so far. Just to be clear this method can't retrieve a .DAT recorded on the flash memory. It only makes it possible to retrieve future flights.

I use the FileZilla FTP client to delete these files. FileZilla can be obtained here
Download FileZilla Client for Windows (64bit)

Setting up FileZilla.
1) Connect USB port to the PC and then start FileZilla
2) In the FileZilla menu bar go to File->SiteManager and create a site called Mavic with these settings. Use 'nopass' for the password.
upload_2018-5-22_6-27-47.png
and
upload_2018-5-22_6-29-19.png

After the Mavic site is set up you can delete files on the Mavic by first connecting to the Mavic
upload_2018-5-22_6-36-10.png

In the Remote site pane navigate to the /blackbox/flyctrl directory by double clicking the blackbox directory then double clicking the flyctrl directory. You should then see the contents of the the /blackbox/flyctrl directory
upload_2018-5-22_6-42-21.png
Now delete some .DATs
upload_2018-5-22_6-43-55.png
I like to leave a couple of the newest FLYxxx.DATs. Removing all of the FLYxxx.DATs will cause the Mavic Pro to start re-numbering at FLY001.DAT.

Now navigate to the /blackbox/vision directory and delete some of the directories found there.
upload_2018-5-22_6-46-8.png
It's unclear which vision directories are associated with which FLYxxx.DAT(s). Here, again, leave a couple of the most recent directories.
 
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Thanks for posting this @BudWalker. Do you think this would be an effective way to remove incriminating flight data after, say, a crash? Assuming, of course, the unit will still power up and connect.

Knock on wood, but after nearly 18 months of ownership, I've yet to have such an event, but inquiring minds wanna know... I wonder too, if there isn't an undelete feature DJI could implement.

Build a better mousetrap, get a smarter mouse.
 
Thanks for posting this @BudWalker. Do you think this would be an effective way to remove incriminating flight data after, say, a crash? Assuming, of course, the unit will still power up and connect.

Knock on wood, but after nearly 18 months of ownership, I've yet to have such an event, but inquiring minds wanna know... I wonder too, if there isn't an undelete feature DJI could implement.

Build a better mousetrap, get a smarter mouse.
This method should remove any trace of a flight. But, it's always possible that there may be other incriminating evidence that I'm unaware of.

Certainly, it would be very easy for DJI render this methodology ineffective.
 
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You mention doing this every 15 or 20 flights? Do we know the capacity of the SD Card? Is there a way to see the SD card percentage full capacity?
 
You mention doing this every 15 or 20 flights? Do we know the capacity of the SD Card? Is there a way to see the SD card percentage full capacity?
I don't have a set number of flights before deleting some files to make room for new flights.The 10 to 20 flights number that I mentioned was just what I remember happening to me. It's hard to estimate how much room is taken up by a flight because there are the vision files in addition to the FLYxxx.DAT. Until we can figure out a set of good practices I'd suggest deleting every 10 flights or so.

There is a way to see the disk usage of SD card. It involves rooting the Mavic and then using ADB to run a shell on the Mavic. Then use the df command. On my Mavic the partition containing the /blackbox stuff is 2.2 G.
 
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In the Remote site pane navigate to the /blackbox/flyctrl directory by double clicking the blackbox directory then double clicking the flyctrl directory. You should then see the contents of the the /blackbox/flyctrl directory

Now delete some .DATs

Now navigate to the /blackbox/vision directory and delete some of the directories found there.
I navigated to the flyctrl directory and there's nothing there. Huh?
Edit: OK. Got to read. Difference between the /flyctrl directory and the /blackbox/flyctrl directory. If I could delete this post I would, but can only edit. Maybe it will slow down others as impatient as me.

I successfully deleted all but three of the files, including one from December 17th 2017 that didn't seem to want to go away. I deleted it again, exited filezilla, started a flight; landed; reconnected to filezilla and VOILA! .dat file was there...along with that rogue December 17th flight. No worries though. It seems to work (and to OP Budwalker): your estimate of about 10 flights seems right. The directory contained about 15 flights of varying lengths before it stopped recording around the end of February. Thank you again.
 
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When I deleted all the previous files, you are correct the next dat was fly001.dat. As you suggest leave at least the most recent dat to maintain sequencing.
 
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Thanks @BudWalker for the nice tutorial and sharing that info. Need to retest it when I will be back home.
 
You mention doing this every 15 or 20 flights? Do we know the capacity of the SD Card? Is there a way to see the SD card percentage full capacity?
I believe the capacity is 4 GB (unless you manually inserted SD card inside the AC and then you know the capacity)
yes, there is a way to find free capacity percentage:
if you take TXT log from your phone/tablet and create CSV file from it using my converter, you can find this information in column named HOME.dataRecorderRemainCapacity
you can also find here which DAT log belongs to that TXT log - it's in column HOME.dataRecorderFileIndex

and thank you, BudWalker, for this information, it's pity that Mavics don't do it the same way as Phantoms do - automatically delete the oldest DATs
 
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I believe the capacity is 4 GB (unless you manually inserted SD card inside the AC and then you know the capacity)
yes, there is a way to find free capacity percentage:
if you take TXT log from your phone/tablet and create CSV file from it using my converter, you can find this information in column named HOME.dataRecorderRemainCapacity
you can also find here which DAT log belongs to that TXT log - it's in column HOME.dataRecorderFileIndex
YIKES!!
 
I believe the capacity is 4 GB (unless you manually inserted SD card inside the AC and then you know the capacity)
yes, there is a way to find free capacity percentage:
if you take TXT log from your phone/tablet and create CSV file from it using my converter, you can find this information in column named HOME.dataRecorderRemainCapacity
you can also find here which DAT log belongs to that TXT log - it's in column HOME.dataRecorderFileIndex

and thank you, BudWalker, for this information, it's pity that Mavics don't do it the same way as Phantoms do - automatically delete the oldest DATs
It's just the Mavics with FW 01.03.0900 and after that have this problem.

And, let me take this opportunity to thank you @ferraript for the work you've done on the TXTlogToCSVtool.
 
It's just the Mavics with FW 01.03.0900 and after that have this problem.
And, let me take this opportunity to thank you @ferraript for the work you've done on the TXTlogToCSVtool.
don't forget there is a lot of modders here who run mixed firmware :D
so the correct information is that this problem exists only with Mavics which have their flight controllers on firmware 01.03.0900 and newer

I'm just doing what I can and I am happy that after more than 2 years it's still working (actually maybe I'm little bit surprised)
I believe you could say something like this too
I have no other option than to return the favour to you, so big thanks to you too ;)

but back to the topic
don't forget to add this valuable information to your datfile website so everything important will be at one place
 
@BudWalker I’m having trouble trying to FTP into my mavic pro, firmware 1.04.300. I’m on a Mac so I’m using a program called cyberduck to FTP in. I see my mavic have an ip of 192.168.42.3, but I can’t connect to it. Do I need a password/user name? Or do I need a special firmware? I can load up Assistant and it connects to my mavic. So is there more steps I need to FTP into the mavic? Thanks.

EDIT . Ok I managed to connect to 192.168.42.2, but I was able to copy some files but some just times out. What can I do to resolve this? Thanks.
 
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@BudWalker I’m having trouble trying to FTP into my mavic pro, firmware 1.04.300. I’m on a Mac so I’m using a program called cyberduck to FTP in. I see my mavic have an ip of 192.168.42.3, but I can’t connect to it. Do I need a password/user name? Or do I need a special firmware? I can load up Assistant and it connects to my mavic. So is there more steps I need to FTP into the mavic? Thanks.

EDIT . Ok I managed to connect to 192.168.42.2, but I was able to copy some files but some just times out. What can I do to resolve this? Thanks.
The procedure is used to delete files and directories on the Mavic Pro. It's not intended to be used as a means to retrieve .DATs.

The time out that you're seeing is due to a bug in the FTP server on the Mavic. But, even if you FTP a .DAT from the Mavic it will be encrypted. Why not just use the DJI Assistant to retrieve the .DATs?
 
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The procedure is used to delete files and directories on the Mavic Pro. It's not intended to be used as a means to retrieve .DATs.

The time out that you're seeing is due to a bug in the FTP server on the Mavic. But, even if you FTP a .DAT from the Mavic it will be encrypted. Why not just use the DJI Assistant to retrieve the .DATs?

Ok thanks for the info. Didn’t realize it was encrypted.
 
That did the trick for me! Thank you!
I was starting to get worried that my logs were simply randomly vanishing (or not appearing at all).
 
I've noticed that the newest FW (01.04.0400) may have fixed the problem where old .DATs aren't deleted when space is required for a new .DAT. Still looking at this.
 
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FW 01.04.0400 has fixed this problem. It's no longer necessary to use this procedure to keep .DAT files accessible.
 
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