Generating and downloading DataFlash Log

HI, I am trying to download a dataflash log, but I keep getting the result that no dataflash logs exist.

My process is arming the vehicle, giving the vehicle a few commands, and then disarming. After disarming, I try to download the dataflash log through Mavlink using Missionplanner, and each time get told that no logs exist.

What am I doing wrong?

By default the logs are not recorded until launch. If you want to record logs right after power up there is a parameter called:

LOG_DISARMED: Enable logging while disarmed

If LOG_DISARMED is set to 1 then logging will be enabled while disarmed. This can make for very large logfiles but can help a lot when tracking down startup issues

Values
Value Meaning


0 Disabled
1 Enabled

Actually I see you are arming. Check your logging level and make sure it includes what you want to watch.

Sorry, what do you mean logging level?

Can you just remove the SD card and use it instead of using Mavlink

I just tried, there is nothing in the log folder. It would seem that nothing is being logged by the pixhawk.

What is LOG_BITMASK set to. I’ll look at my parameter list.

I think he means LOG_BITMASK when saying logging level

Indeed.
The LOG_BITMASK parameter controls what message types are recorded in the dataflash. Recent versions of the mission planner and ArduPilot allow individual messages to be enabled/disabled from the MP’s Config/Tuning, Standard Params screen.

Check out:
http://ardupilot.org/copter/docs/common-downloading-and-analyzing-data-logs-in-mission-planner.html?highlight=log_bitmask

Oddly I don’t see it in the complete parameters list, like they changed the name or something.

I’m using 3.4b in one boat and it is still there. set to 65535.

Hmm, so that is what it is set to for me as welll… What are your other logging parameters?

LOG_BACKEND_TYPE,1
LOG_DISARMED,0
LOG_FILE_BUFSIZE,16
LOG_FILE_DSRMROT,0
LOG_MAV_BUFSIZE,8
LOG_REPLAY,0

That all them.

It begs the question what version of Ardupilot are you running for which vehicle? Also if your SD has problems you may not get logs at all. Try a different one formatted to fat32.