Allow user to display logged GPS Data

[ctzsnooze]

Currently, blackbox_disable_gps is set to OFF by default, so we should expect GPS data to be saved to the log when GPS data is available, and to be able to review that data in Blackbox Log Viewer.

In blackbox/blackbox.c there are many references to logging GPS data.

I can't follow the code well enough to know if GPS data is truly being added to the log, but it appears most of it has been implemented.

When GPS is enabled, the log header will show something like this:

H Field G name:time,GPS_numSat,GPS_coord[0],GPS_coord[1],GPS_altitude,GPS_speed,GPS_ground_course
H Field G signed:0,0,1,1,0,0,0
H Field G predictor:10,0,7,7,0,0,0
H Field G encoding:1,1,0,0,1,1,1

It seems, as best I can tell, that these GPS frames are being included in the logs, by default, but cannot be displayed in Blackbox, and is not included in a CSV export. So there is no way to know if the data is there, or to retrieve and use it.

This data is really useful when debugging GPS rescue, but also for knowing groundspeed (how fast can I go), for mapping where the quad has been, monitoring satellite count, and so on.

The problem:

It is impossible to retrieve the data from the log.

The decoder for these fields was never implemented. Some notes exist in the existing blackbox code here. It looks like this was never completed.

Seeking help!

It would be fantastic, and much appreciated, if someone could parse these fields, and provide a means to:

• graph
• export into CSV
• display raw values in the info page

It would be absolutely great if we could see and use this data.