Thanks for the help! I got it working nowā¦
Short summary below in case it helps someone else.
Tried as suggested, and interchanged the TX/T1 and Rx/R1, did not work either, but it made me look really hard at the pinouts and connections and I think that did reveal something odd.
In the version of the HD-Zero manual I am using ( v0.5, the at the moment current one from the hd zero website ) there is a table with the pinouts for the freestyle vtx on page 10. I think there is something wrong with that table.
It lists from top to bottom āground power rx tx saā. However the supplied cable uses colors āred black yellow green blueā, which is inconsistent with the table, and I was powering the vtx with red wired to v_bec and black to gnd and it works in the sense that it transmits good video.
Went to watch some installation videoās where they use the ālogicalā sequence suggested by the cable colorsā¦ which makes me I think both ground and power and rx tx are swapped in that table.
This did not solve my problem because I tested it already with your suggested test, but I went ahead and soldered the newly assumed tx (yellow) to R4 and assumed rx (green) to T4. Changed Serial1_protocol to -1 and Serial4_protocol to 42, Serial4_baud to 115, other osd related settings as described in the previous messages. Powered up and this works! very pretty lettering on the screen
In summary, I have no idea why T1/R1 do not work on my fc, but if I connect rx/tx in the right order to R4/T4 + suggested serial settings the osd works fine.
Anyways, hope this helps someone & thanks for the support!
Iām off to the field, there is no wind and the sun is out.
The table in the manual for the Freestyle VTX does not describe the sequence, but only the cable colors with which function. At least thatās how I understood, connected and just worked right away.
If it works now it is great. Enjoy the HD flights ā¦
Flights were great! Definitely an upgrade wrt analog.
Strange that in this case my work experience worked against troubleshooting this.
I am used to never trust wire markings or colors, but to go from rail / connector / socket order or numbers. But I guess sometimes things work differently, different assumptions to start withā¦
But problem solved, works great, thanks for the help!
Thanks Boris, good to hearā¦actually I just need to change the power to pitmode or lower the power to prevent from over heating while waiting for GPS fixā¦ OSD im okay and happy with itā¦
but let me try that inverting the pitchā¦ thanks for the inputs.