MSP_OSD code changes to support OpenIPC, DJI O3, and other digital VTX OSD

[Li-Tianming]

There are many questions about the unavailability of MSP_OSD. I had same
problems.

MSP OSD support for Walksnail VTX and AVATAR goggles

I am trying to integrate OSD messages from a Pixhawk 6C mini (Firmware version 1.14.3) with Walksnail VTX to be displayed on AVATAR googles X. I see OSD related parameters in the doc (Parameter Reference | PX4 User Guide (v1.14)), but its not visible when I check the parameters of the Pixhawk from QGC. Following MAVLink Peripherals (GCS/OSD/Companion) | PX4 Guide (main), I enabled OSD on mavlink-1 for telem-2 at 57600 baud rate, but I don’t see anything in the goggles. Are there any other param…

Help Setting Up DJI O3 Air Unit with OSD on PX4 1.15 (MSP_OSD)

Hi everyone, I’m trying to set up the DJI O3 Air Unit with OSD on PX4. I’ve flashed version 1.15 with MSP_OSD enabled and connected the DJI O3 Air Unit to TELEM1. However, I’m only seeing the main battery voltage displayed on the OSD—no other telemetry data appears. Interestingly, when I tested the same setup with a Caddx Vista, the OSD works as expected, showing all relevant telemetry data. Does anyone have experience with the DJI O3 Air Unit and PX4 MSP_OSD? Is there a specific configuratio…

Help in Nxt-Px4V2

Greeting! I’ve just successfully used ELRS-MAVLink for telemetry. It’s quite simple MAVLink - ExpressLRS can be helpful. Note that both the Tx and Rx should be running ELRS version >3.5. After updating, you can simply modify a few parameters of PX4 in QGC, and everything should work. Good luck! I’m also looking for solutions for OSD because I couldn’t get my Avatar HD to work with PX4 (no OSD information on the screen, although the msp_osd status seems fine).

After some research and code reading, I found that the MSP_OSD rendering process of PX4 is very different from the latest Betaflight and Ardupilot

MSP OSD support for Walksnail VTX and AVATAR goggles

The message function filed( message[4] ) in betaflight and ardupilot are all B6(182) // External OSD displayport mode messages #define MSP_DISPLAYPORT 182 But this filed PX4 every one is different [image] I have analyzed the MSPOSD drawing process of the latest betalight. [image] If you want to draw the pitch in OSD, such like in the picture above. The complete data flow is as below. it’s base on subcmd in the message[5]. 24 4D 3E 01 B6 00 B7 // Release the display a…

After comparing the Betaflight and OpenIPC MSPOSD code, I modified the code of PX4 MSP_OSD, and the OSD now can be rendered.

PX4-Autopilot/src/drivers/osd/msp_osd at v1.15.4-br_osd_mod ·...

The current code are only examples and have not been completed. Full support may take some time.

My testing equipment is OpenIPC and O3/O4 Air unit.
It has already been tested in OpenIPC. I will test it on O3/O4 in the future

[dakejahl]

Thanks for looking into this. If you get it fixed up and working can you submit a PR?

[Li-Tianming]

Definitely I will.

[Li-Tianming]

Tested on DJI O3 Airunit and it’s OK （2025-04-07）

[Li-Tianming]

I have completed the modification of MSPOSD function
The final rendering effect is as bellow:

The current OSD can already cover a lot usage scenarios. So, I have opened PR.
If there have any suggestions or modifications, I would be like to continue following up

MSP_OSD code changes to support OpenIPC, DJI O3, and other digital VTX OSD

[dakejahl]

Awesome thank you! I will check it out

[alnI3S]

Thank you very much @Li-Tianming,

You did a nice work for the community.

I’m also working by porting Audupilot msp osd to PX4 by creating a new protocol for osd devices instead of modifying the existing PX4 code. There are 107 osd symbols instead of 22 for PX4 for now. Your work help me to simplify the porting.

Thanks again