Results are different when downloading logs through Mission Planner and downloading logs through MavProxy

Results are different when downloading logs through Mission Planner and downloading logs through MavProxy.

The details are as follows.

  1. Load module dataflash_logger in Mavproxy

  2. Flight drone

  3. I can see the log file is created on the CC board in real time.

  4. Finished to flight.

  5. Connect drone fc with PC in mission planner.

  6. Download Dataflash Log Via Mavlink.
    image

The file created from mavproxy and the file downloaded by mission planner are not same…

And, the size of file downloaded by mission planner is bigger than the file created from mavproxy…

Why is this so?

It’s a bug which I have fixed, fingers crossed it might make it into 4.0 sometime soon …

Thank you for your response.

First, I would like to know exactly what bug you have.

And I would like to know when the release date for the modified version you are talking about is.

The fix has been merged into master. It fixes a number of issues along the lines that you describe.

Thank you for your kind reply.

I tried to check the Ardupilot v4.0.1-dev(4a688e59) firmware on the Pixhawk 2 CubeBlack, but the issue was still coming out.

The details are as follows.

*Note that no sensors are connected to the FC board for testing purposes.

[Case1. Ardupilot v4.0.1-dev(4a688e59) firmware on the Pixhawk2 CubeBlack]
The parameter values related to logging are as follows.
image

  1. Logging was performed on the CC board connected to FC board through the dataflash_logger module included in Mavproxy. As a result, the log file size is 1825000 bytes
    image

  2. If I check the log file size recorded on the SD card of FC board through Mavproxy, the log file size is 3266725 bytes
    image

  3. Attach log files for reference.
    12.BIN by dataflash_logger : https://drive.google.com/open?id=1m0rBzR23HFAEyyfXCcxqt-ADzJjsDO6d

    log1.bin by FC SD Card : https://drive.google.com/open?id=14UhSKmsJmEpMejiO9WbGDeeudtoRvVPe

[Case2. Ardupilot v3.6.2 firmware on the Pixhawk2 CubeBlack]
The parameter values related to logging are as follows.
image

  1. Logging was performed on the CC board connected to FC board through the dataflash_logger module included in Mavproxy. As a result, the log file size is 726000bytes
    image

  2. If I check the log file size recorded on the SD card of FC board through Mavproxy, the log file size is 195584bytes (Result after deleting all logs by “log erase”)
    image

  3. Attach log files for reference.
    13.BIN by dataflash_logger : https://drive.google.com/open?id=13XTbKaSi61-DULFkVc-ix_qgscX5qyyx

    log1.bin by FC SD Card : https://drive.google.com/open?id=1rUf5GTe6CDAJZG4G4z72QnIXim3k_XtW

I have another question.

Is it correct that the timeus value from log downloaded from the FC board and the timeus value from log collected by dataflash_logger in mavproxy are different from each other?

Logging was performed on the CC board connected to FC board through the dataflash_logger module included in Mavproxy. As a result, the log file size
is 1825000 bytes
image

Well, it’s cool that dataflash_logger is working for you. But the data
that you get from this will NOT be the same as that you get from
downloading the logs; they do log slightly different things. (DFS and DMS
messages).

If I check the log file size recorded on the SD card of FC board through Mavproxy, the log file size is 3266725 bytes
image

OK, that disparity is a little too large. You’re dropping vast numbers
of packets (See DMS.N and DMS.Dp) - almost certainly because your serial
baudrate is too low and the data simply cannot be shifted fast enough.

Peter

Thank you for reply.

What is DFS and DMS? I don’t know it.

What is the abbreviation?

But the data that you get from this will NOT be the same as that you get from downloading the logs; they do log slightly different things

Could you send us some pointers as to where it is defined in the code what gets logged and how it’s different for File vs Mavlink? Thanks