Support via_BetaflightPassthrough with Ardupilot

[CapnBry]

Ardupilot can do passthrough serial as well and if configured manually (holding the boot button and setting the passthrough manually) has worked for a user so 420000 baud passthrough should work.

Needed

• Connect to Ardupilot (baud rate might be anything from 1200 to 1500000) and query SERIALx_PROTOCOL (x = 1-8) and look for which has a value indicating it is CRSF (29)
• Set SERIAL_PASS2 to the x discovered to be CRSF
• May need to set SERIAL_PASSTIMO to set the timeout for the port to revert back to Ardupilot. 0 is forever, value is in seconds.
• Upload away!

Ardupilot Documentation
Serial Passthrough
All parameters

[brandonrc]

@CapnBry are you saying someone has actually flashed ELRS with Ardu? I attempted this but could not get it to work. Got some weird Errors. I Will try it again.

[CapnBry]

Yes but they did it all manually by holding down the boot button on the RX, powering, then setting SERIAL_PASSTIMO and SERIAL_PASS2 and using the UARTUpload.py script.

[aLDime]

• SERIALx_PROTOCOL (x = 1-8) and look for which has a value indicating it is CRSF (29)>
  And https://www.expresslrs.org/1.0/software/updating/betaflight-passthrough/#ardupilot-instructions-community-contribution-untested

`Result

Flash error
*** [upload] Error 2
========================= [FAILED] Took 20.00 seconds =========================
Environment Status Duration

---

DIY_900_RX_ESP8285_SX127x_via_BetaflightPassthrough FAILED 00:00:19.998
==================== 1 failed, 0 succeeded in 00:00:19.998 ====================
Actions`