Wireless Modem

Modem
Item ID	???
Damage Value	???
Peripheral?	Yes

Modems are blocks which can be used to wirelessly transfer data between computers and turtles, using the Rednet API. To place a modem on a side of a computer, right-click to place the modem while sneaking.

It is also possible to turn the modem on and off by typing "rednet.open ( side )" to open and "rednet.close ( side )" to close.

Modems can send messages to other modems located up to 64 meters away, or 16 meters during a thunderstorm. As of 1.4 Modem range is increased with higher altitudes. If there is no thunderstorm, the range will always be higher than 64, and at max altitude you would have a range of 384 meters.

In 1.4 and 1.41 there is a miscalculation that causes the range to only be 381 meters at max altitude.

Recipe

Example

• Place 2 computers and add modems to them by clicking the right mouse button while sneaking.
• Access them, and start Lua.
• Once Lua has started, type "rednet.open ("<relative location to modem, e.g. left, right>")" on both computers.
• Check if there exists a connection: a dim, red light should be found on the modem.
• Type on one computer "rednet.receive (60)". This will make the computer freeze for 60 seconds, or until it has received a signal from the other computers.
• Now, type "rednet.broadcast ('<your message>')" on the other computer. This should send your message to all computers connected.
• Opening the first computer should show the message written on the second computer.

Modem as a Peripheral

To use a Modem as a peripheral, you need to either call a method directly using peripheral.call(), or, wrap the modem using the Peripheral API. Wrapped modems provide all functions listed in the Rednet API.

For this example, we have a Modem connected to the top of our Computer:

-- Immediately invoke a method without wrapping
peripheral.call("top", "open")

-- You can also "wrap" the peripheral side to a variable:
local modem = peripheral.wrap("top")
modem.open("top")