broadcast-to-linked-card-relay for microcontroller

relay.lua

--Uses line-separated key=value pairs for configuration in the eeprom data section
--Available settings: `inputOnly`:boolean, `outputOnly`:boolean, ports:comma-separated-list
local function splitter(str, sep)
	if sep == nil then sep = "%s" end
	local t={}
	for string in string.gmatch(str, "([^"..sep.."]+)") do table.insert(t, string) end
	return t
end

local tunnel = component.list("tunnel")()
if tunnel then
	tunnel = component.proxy(tunnel)
else
	error("No tunnel component found. Install linked card.")
end
local modem = component.list("modem")()
if modem then
	modem = component.proxy(modem)
else
	error("No modem component found. Install network card.")
end
local redstone = component.list("redstone")()
if redstone then
	redstone = component.proxy(redstone)
end

local settings_str = component.proxy(component.list("eeprom")()).getData()
local settings = {}
if settings_str then
	for _,v in ipairs(splitter(settings_str, "\n")) do
		local set = splitter(v, "=")
		settings[set[1]] = set[2]
	end
end

if settings.ports then
	for _,port in ipairs(splitter(settings.ports,",")) do
		modem.open(tonumber(port))
	end
end

computer.beep("..")
while true do
	local signal = {computer.pullSignal(1)}
	if signal[1] == "modem_message" then
		local event, receiver, sender, port, distance = table.unpack(signal)
		local data = {select(6, table.unpack(signal))}
		if not settings.outputOnly and port ~= 0 then
			tunnel.send(port, table.unpack(data))
		elseif not settings.inputOnly then
			modem.broadcast(data[1], select(2, table.unpack(data)))
		else
		end
	end
end