Ardupilot2/ROMFS_custom/scripts/led-control.lua

-- led-control.lua: Control serial LEDs with ArduPilot parameters and RC switch

-- Constants
local PIXEL_GROUPING = Parameter("PIXEL_GROUPING", 1) -- LEDs per arm
local PIXEL_DEFAULT = Parameter("PIXEL_DEFAULT", 0)  -- Default behavior (0: arming-based, 1: always active)
local PIXEL_ARM = {
    Parameter("PIXEL_ARM1", 1),
    Parameter("PIXEL_ARM2", 1),
    Parameter("PIXEL_ARM3", 1),
    Parameter("PIXEL_ARM4", 1)
}
local RC_SWITCH_CHANNEL = 300 -- Use RC channel set in ArduPilot parameters
local AuxSwitchPos = {LOW=0, MIDDLE=1, HIGH=2} -- Switch positions

local RGB_COLORS = {
    {0, 255, 0},  -- Green
    {255, 0, 0},  -- Red
    {255, 255, 255},  -- White
    {128, 0, 128}  -- Purple
}

local NUM_ARMS = 4
local prev_pos = -1
local leds_enabled = true

-- Initialize serial LED channel
local led_chan = assert(SRV_Channels:find_channel(94), "LED: channel not set") + 1
gcs:send_text(6, "LED strip: chan=" .. tostring(led_chan))
assert(serialLED:set_num_profiled(led_chan, 8), "Failed LED setup")

-- Validate parameters to ensure safe behavior
local function validate_params()
    if PIXEL_GROUPING:get() < 1 then
        gcs:send_text(3, "Invalid PIXEL_GROUPING. Defaulting to 1.")
        PIXEL_GROUPING:set(1)
    end

    for i = 1, NUM_ARMS do
        local arm_behavior = PIXEL_ARM[i]:get()
        if arm_behavior < 1 or arm_behavior > #RGB_COLORS then
            gcs:send_text(3, "Invalid PIXEL_ARM" .. i .. ". Defaulting to 1 (Green).")
            PIXEL_ARM[i]:set(1)
        end
    end
end

-- Set LEDs
local function set_leds(color, start, count)
    for i = start, start + count - 1 do
        serialLED:set_RGB(led_chan, i, color[1], color[2], color[3]) -- RGB values
    end
end

-- Update LED behavior
local function update_leds()
    local armed = arming:is_armed()
    local grouping = PIXEL_GROUPING:get()

    for arm = 1, NUM_ARMS do
        local behavior = PIXEL_ARM[arm]:get()
        local color = RGB_COLORS[behavior]

        -- Default to red if disarmed and PIXEL_DEFAULT is 0
        if not armed and PIXEL_DEFAULT:get() == 0 then
            color = RGB_COLORS[2] -- Red
        end

        local start_idx = (arm - 1) * grouping
        set_leds(color, start_idx, grouping)
    end

    serialLED:send(led_chan)
end

-- Main update loop
local function update()
    -- Get the current RC switch position
    local sw_pos = rc:get_aux_cached(RC_SWITCH_CHANNEL)

    if sw_pos == nil then
        gcs:send_text(3, "RC_SWITCH_CHANNEL not configured.")
        return update, 1000
    end

    if sw_pos ~= prev_pos then
        if sw_pos == AuxSwitchPos.LOW then
            leds_enabled = false
            serialLED:clear(led_chan)
            gcs:send_text(6, "LEDs turned OFF")
        elseif sw_pos == AuxSwitchPos.MIDDLE then
            leds_enabled = true
            gcs:send_text(6, "LEDs turned ON (Dimmed)") -- Dimming logic can be added later
        elseif sw_pos == AuxSwitchPos.HIGH then
            leds_enabled = true
            gcs:send_text(6, "LEDs turned ON (Full Brightness)")
        end
        prev_pos = sw_pos
    end

    if leds_enabled then
        update_leds()
    end

    return update, 1000 -- Run every 1 second
end

-- Initialization
serialLED:clear(led_chan)
validate_params()
if leds_enabled then
    update_leds()
end

return update()