[chromvis]

I was trying to log in-flight parameters (voltage, current, vibrations, etc.) through OpLink-Bluetooth config on latest Next build (r812)
Did not get anything.
Is any loging configuration manual or description of basic principles exist any where? I could not find any.
There seem so be logging settings in DebugLogSettings, but I am not sure if it could be used for transmission via OpLink, or it is for logging on FC itself (which I do not need).
How telemetry transmitted to GCS could be logged selectively (How I can select what I want to save?)
I appreciate any information.

[f5soh]

Take a look here for Scopes:
https://librepilot.atlassian.net/wiki/display/LPDOC/Scope+Tab

In options there is a checkbox for CSV file output.

[chromvis]

Yes, I saw it. How is it related to Ctrl+L command? does it mean that it will log only the data for which i mark the checkbox?
Is it possible to control data frequency? How?
Is it possible to activate logging with arming command and stop log at disarm?
What means "data size"? Is it logging time, or accuracy, or scale on the scopes?
In Options -> Scopes there is no battery/power data, coordinates, and many other useful parameters. Is there a way to log them also?

[f5soh]

Start logging (Ctrl+L) : record all uavo activity, allow log replay later. Nothing related to Scopes.

Data frequency: maybe you mean update interval ?
wiki says: Update interval : Can't be faster than lowest refresh rate in UAVObjects used.
Refresh rate can be set in UAVOBrowser, need to display metadata (click the icon with a eye)
Remember this is a radio link and faster refresh rates increase the bytes/s

From wiki, Data size : the 'window' for scope so just for scope display.

Every uavo data can be logged, no restrictions. Just pick the UAVO you want in your scope, and this data is finally logged in CSV file.
Current scopes already configured are examples, you can setup the scope you want.
On top, the scope name as displayed using Edit Gadget mode. The clone button can be used to start a new custom scope.

[chromvis]

Thank you. I did not realize that it is configurable. Will try. So far I got csv file with only column titles and no data, but may be I did something wrong.
Thanks again.

[TheOtherCliff]

Logging gets all the UAVOs that are received in real time on the GCS.  Any of these UAVOs can be configured to display using a scope on the scope page. Typically we log a flight and later play it back to watch what happened on the scopes, add some more scopes, play it back again, etc.

The System page has an eyeball with an option that will allow you to see the UAVO metadata.  The Metadata allows you to change how often the data is sent from the FC to the GCS (etc).  Don't make too many send too fast or telemetry will collapse because there is too much data for the telemetry data rate.  You can increase the telemetry data rate if needed.  I usually just stay with telemetry at 57600.

[chromvis]

I was trying today to start logging (Ctrl+L) but got empty file. Logging though scopes (.csv files) works, but I did not quite get what triggers stopping and starting log and data frequency is about 1/sec at best. On one test I got about 8 small files.

[TheOtherCliff]

Your telemetry must be working and receiving data for logging to work.  The Tx and Rx bar graphs at the bottom of the page should show activity.  In particular, the Rx one should constantly show above 2000.  The default Scope page should show good, moving graphs.

If you are using RF telemetry you should increase the OpLink data rate to at least 57600.

You may try Tools->StartLogging instead of Ctrl-L?

[chromvis]

OK. I got .csv files no problem, but they are too slow. Max refresh frequency that I got is 1 Hz.
Ctrll+L or Tools>StartLogging initiate different process apparently and produce .opl file. This may be better, because I can modify logging parameters in Meta data section. I tested it and got 78Kb .opl file.
The only obstacle - I have no idea how to read it?
I could not find anywhere how to read, play, or visualize somehow.
I appreciate any information.

[f5soh]

You can load the csv files using a excel like software and generate the graphs you want.

[hwh]

...78Kb .opl file.
The only obstacle - I have no idea how to read it?...

The .opl file is a binary log file, the entire raw telemetry stream.  GCS itself can play it back.  In the lower right of the screen where it usually connects to a cc3d/revo via USB you can select a log file instead.  Do it without a board connected. The system tab has a "player" that can start/stop playback.  It has problems and can't actually stop or restart playback.  There's an open issue in Jira to fix it.  You can play a log file as it is and GCS acts like during the actual flight.

[f5soh]

About refresh: there is the meta refresh values and the update rate in scope options.

If you set like 300ms in both places you get a 300ms rated csv file.
Scope options tell you if you set a too small update rate value according to the UAVO/Meta refresh value you add to scope.

[chromvis]

Thank you hwh, I tried it and it works.
I was struggling today with external magnetometers and GPS on two systems, one with revo and another with Sparkey2. Finally end up replacing Neo-8N with Neo-7N and it gets better, but still I want to check variations myself including vibration. BTW, I am using autotune routinely on all systems, no problem so far.
Regarding refresh rate and update period. In Data objects there are "Flight telemetry Update Period"; "GCS Tel. Update period", and "Logging Update period". How they are related to logging using Ctr+L command and Logging into .csv file. There are also "Modes" with boolean parameters that seems to enable or disable different types of updates (eg. periodic, or on change).

Thank you f5soh. Again, there are 3 different update rate parameters in meta data, and which one is related to logging into .csv file and which is related to logging into .opl file?
I think that OPlink transmission is also a limiting factor. I am using 57600, 115000 did not work for some reason.
About a month ago I set Oplink for PPM+telemetry with bluetooth connection to laptop. After reading one post here (luckily before I flew far) I tested signal strength by just walking away and found that in 20 - 30 m signal strength (blue vertical bar on OpLink tab) went down to -128 dB  (35 was absolute maximum working distance). I do not know if it was too much for this radio to transmit PPM and telemetry? I just set SBus receiver to avoid flyaway.

[f5soh]

Again, there are 3 different update rate parameters in meta data, and which one is related to logging into .csv file and which is related to logging into .opl file?

You should modify the one that already set ?
Those rates apply to opl and also for csv.
The update rate in scope options need to be > to all rates from all uavo added to the scope.