SmartAudio not working, VTX power in OSD is blinking -- any way to debug?

Hi, I’ve got a Matek H743-wing-v2 with a Rush Ultimate Plus VTX. I’m trying to configure serial4 (aka pin Tx3 on the board) for SmartAudio, but when I power everything on the VTX stays in pit mode and the VTX power setting in the OSD just blinks the set power but it doesn’t actually take effect.

If I change the VTX_POWER option in Mission Planner and write the params out to the board, the power setting in the googles doesn’t change. If I then reboot the board the new power setting show up blinking in the goggles.

I’ve attached my config file.

Is there any way to enable logging to see what’s going on?

ardupilot_h743_wing_v2_explorer.param (21.5 KB)

Hello Chris,

This is a bit of an old post, so I presume you’ve sorted it. But I just wanted to say I just got this working and the only difference I can see on my settings is that I had SERIAL4_OPTIONS set to 4 and you seem to have yours set to 68. ie. you have selected TX_Pulldown and I have only selected HalfDuplex.

It’s been very cool. With RC10_OPTION set to 94 and Channel 10 set to a Pot I am able to turn my VTX from Pit Mode all the way up to full power using my Pot which has a natural feel to it.

Good luck!

Are you using the Rush Ultimate Plus VTX? I actually used an Arduino Nano to make a simple oscilloscope and determined that my VTX was using one stop bit instead of the two that the protocol requires. I had to build a custom load to get it working at all.