MikeBland / mbtx

er9x/ersky9x radio firmware
GNU General Public License v2.0
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Add LTM Telemetry support #22

Open sppnk opened 8 years ago

sppnk commented 8 years ago

Feature request to include native LTM (Light Telemetry) support in er9x.

LTM fits low baudrates like 1200/2400 bauds over long range transmission like OpenLRSng transparent serial link, or FSK modem trough fpv Video TX Audio channel.

LTM is supported by Cleanflight, INAV, amv-open360tracker, Gettostation and other platforms.

Here a link to infos on LTM:

https://github.com/stronnag/mwptools/blob/master/docs/ltm-definition.txt

https://github.com/iNavFlight/inav/wiki/Lightweight-Telemetry-(LTM)

And here a definition from Cleanflight doc on telemetry:

"LTM is a lightweight streaming telemetry protocol supported by a number of OSDs, ground stations and antenna trackers.

The Cleanflight implementation of LTM implements the following frames:

G-FRAME: GPS information (lat, long, ground speed, altitude, sat info) A-FRAME: Attitude (pitch, roll, heading) S-FRAME: Status (voltage, current+, RSSI, airspeed+, status). Item suffixed '+' not implemented in Cleanflight. O-FRAME: Origin (home position, lat, long, altitude, fix) In addition, in the inav (navigation-rewrite) fork:

N-FRAME: Navigation information (GPS mode, Nav mode, Nav action, Waypoint number, Nav Error, Nav Flags). LTM is transmit only, and can work at any supported baud rate. It is designed to operate over 2400 baud (9600 in Cleanflight) and does not benefit from higher rates. It is thus usable on soft serial."

MikeBland commented 8 years ago

The MEGA64 version of er9x has insufficient flash space to add this. It should be possible on the '128 version.

sppnk commented 8 years ago

Could it fit in a new version removing FrskyD protocol and replacing with LTM?

MikeBland commented 8 years ago

The problem then is it adds a number of extra builds as there are several languages to consider as well as the option of original or serial voice. These all need building, testing and releasing. Can you compile the source yourself?

sppnk commented 8 years ago

Yes, I guess I could do. And test it. Thx.

TeNoRek commented 8 years ago

I am for the idea of LTM telemetry support in er9x. I also have M64 based radio, so unfortunately I also support the idea of creating another build version without FrSky telemetry. Looks like LTM is becoming a standard for telemetry https://github.com/ShikOfTheRa/scarab-osd/issues/219

ahmedkelbanna commented 6 years ago

LTM support please . Im trying so hard to do it myself but i'm facing compiling errors . Also i'm still a beginner in coding :D