Direct Messaging

Lua chips on the same data network can send messages to each other. All networking is server-authoritative and scoped to the physical data cable network (including bridged networks).

Setup

-- Get your own endpoint ID (the housing's ReferenceId)
local myId = ic.net.id()
print("My endpoint: " .. tostring(myId))

-- List all Lua chip peers on the network
local peers = ic.net.peers()
for _, p in ipairs(peers) do
    print(string.format("  Peer: %s (id=%d)", p.name, p.id))
end

Sending Messages

-- Send to a specific target by name (set via labeller on the housing)
ic.net.send("ReceiverChip", "alerts", { temp = 300, status = "critical" })

-- Send to a specific target by ReferenceId
ic.net.send(targetId, "alerts", "Hello!")

-- Broadcast to ALL Lua chips on the network
local delivered = ic.net.broadcast("status", { online = true })
print("Delivered to " .. delivered .. " peers")

Receiving Messages

Option A: Handler Function (Recommended)

-- Register a listener for a channel
ic.net.listen("alerts", function(fromId, fromName, payload)
    print("Alert from " .. fromName .. ": " .. tostring(payload))
end)

-- Handler by name (persists better across save/load)
function onAlert(fromId, fromName, payload)
    print("Alert from " .. fromName)
end
ic.net.listen("alerts", "onAlert")

-- Unregister
ic.net.listen("alerts", nil)

Option B: Poll-Style

while true do
    local fromId, fromName, channel, payload = ic.net.recv()
    if fromId ~= nil then
        print("Message on " .. channel .. " from " .. fromName)
    end
    yield()
end

Channel Rules

Rule	Detail
Type	Strings (e.g. "alerts", "sensor_data")
Integer channels	Treated as "1000" (string conversion)
Max payload size	128 KB (MessagePack encoded)
Supported types	nil, boolean, number, string, table
Unsupported	Functions, userdata, cyclic tables

Function Reference

Function	Returns	Description
ic.net.id()	number	Get own endpoint ID
ic.net.peers()	table[]	List all Lua chip peers
ic.net.send(target, channel, payload)	—	Send to target (name or ID)
ic.net.broadcast(channel, payload)	number	Broadcast to all peers
ic.net.listen(channel, handler)	—	Register/unregister listener
ic.net.recv()	fromId, fromName, channel, payload	Poll for messages