VTX Power switching via transmitter switch (Opentx/Betaflight/Tramp/Smartaudio)

vtx.lua

-- *Fixed version of JosefB87 for OpenTX 2.2.4
--
-- *Fixed version of wkochFPV for BF 3.5
-- Original: https://github.com/betaflight/betaflight/issues/3094#issuecomment-302953603
-- Note: If you put it on a 3-way switch and go from first to third position fast it may not register correctly so better step through slowly
--
-- *Changes:
-- Changed played soundfiles using new soundfile naming pattern since Open TX 2.2.4
-- Corrected loading of dependencies
-- Shortened filename to make it compatible with latest opentx restrictions
-- Added a condition in the script for pit mode (vtx power 0 alone didn't work for me)
--
-- *How To (Copy pasted from comment)
-- 1. Install betaflight-tx-lua-scripts as usual
-- 2. Install my script vtx.lua in /SCRIPTS/MIXES
-- 3. In model menu of your taranis go to LUA-scripts page and enable VTXprog.lua and configure as follows:
-- 4. Enter your desired band: 1="A", 2="B", 3="E", 4="F", 5="R" (unify pro!)
-- 5. Enter your desired channel: 1,2,3…
-- 6. Select “global variable 1” (GV1, or another free global variable) as input for TxPower
-- 7.Now configure any switch to adjust GV1 to the desired power level: 0=pit mode, 1=25mW, 2=200mW … (use special functions menu, select ‘adjust GV1’ as action, enter desired value). Use e.g. 0 for your switch neutral position, 1 for switch up, 2 for switch down, if you would like to select 25mw or 200mw based on switch position.
--

-- Load MSP smartport library

SCRIPT_HOME = "/SCRIPTS/BF"

protocol = assert(loadScript(SCRIPT_HOME.."/protocols.lua"))()
radio = assert(loadScript(SCRIPT_HOME.."/radios.lua"))()

assert(loadScript(radio.preLoad))()
assert(loadScript(protocol.transport))()
assert(loadScript(SCRIPT_HOME.."/MSP/common.lua"))()
-- define inputs
local inputs = {
        { "TxPower", SOURCE},                -- store requested TxPower in global variable, e.g. GV1
        { "TxBand", VALUE, 1, 5, 4 },
		{ "TxChannel", VALUE, 1, 8, 1 }
    }

-- Variables to store parameters last programmed to vtx
local lastPower = 0
local lastBand = 0
local lastChannel = 0

local MSP_VTX_SET_CONFIG = 89
local firstrun = 1

-- Returns payload to send to fc
local function VTXconfig(TxPower, TxBand, TxChannel,TxPitMode)
   local channel = (TxBand-1)*8 + TxChannel-1
   return { bit32.band(channel,0xFF), bit32.rshift(channel,8), TxPower, TxPitMode }  -- last 0 disables PIT mode
end
	
local function run(TxPower, TxBand, TxChannel)
    
	-- ignore any settings on first run of the script, send only further changes to vtx
	if firstrun == 1 then
		lastPower = TxPower
		lastBand = TxBand
		lastChannel = TxChannel
		firstrun = 0
	end
	
	if (lastPower ~= TxPower) or (lastBand ~= TxBand) or (lastChannel ~= TxChannel) then
		
		if TxPower > 0 then
			mspSendRequest(MSP_VTX_SET_CONFIG,VTXconfig(TxPower, TxBand, TxChannel,0))
			if TxPower > lastPower then
				playFile("gearup.wav")
			else
				playFile("geardn.wav")
			end
		else
			mspSendRequest(MSP_VTX_SET_CONFIG,VTXconfig(TxPower, TxBand, TxChannel,1))
			if TxPower > lastPower then
				playFile("gearup.wav")
			else
				playFile("geardn.wav")
			end
		end
		
		lastPower = TxPower
		lastBand = TxBand
		lastChannel = TxChannel
	end
	
	mspProcessTxQ()
	
    return
end

return {input=inputs, run=run}

This worked for me really well on my qx7.
I have just got an xlite, and it doesn't seem to be working.
Also any idea how I can make it just change the power and not the band or channel?
thanks heaps.

I have no LUA-scripts page in my model menu, can you please explain a little more in detail how to set it up?

you need to tick Lua in companion when flashing your radio

but I cant get this to work with latest opentx anyway. not getting any response to my above question

you need to tick Lua in companion when flashing your radio

I'm using OpenTX 2.4 nightly from TBS for the crsfshot, is there a way to make it work with it?

There is a luac enabled with this firmware, I can go to the radio menu -> sd card, and execute the script from there isn't it the same?

try it with OpenTX 2-3-9. will not work.

try it with OpenTX 2-3-9. will not work.

I have the same problem. I can't assign inputs for the scripts. Are anyone find a solution?

Yes! this is actually a feature of betaflight now.
you can find the cli commands to set this up without lua scripts.
It works much better
https://github.com/betaflight/betaflight/wiki/VTX-CLI-Settings
Check out this page.
Let me know if you have any issues.

Yep, you can set it up using Betaflight and its a way better solution, LUA scripts you have to keep maintained with every new open TX release it seems. This was available in Betaflight all along BTW, but most didn't know about it. Heres a great tutorial from Bardwell: https://www.youtube.com/watch?v=a1_U2v0kAjg