Radio¶ ↑

Created by Kelly Egan on 4/30/10.

This library is indebted to the RF12 library created by Jean-Claude Wippler @ Jee labs jeelabs.net It is substantially different than the his library particularly in packet structure and that it is now a C++ class. I also attempted to additionally comment the source code mostly for my own understanding.

The MIT License¶ ↑

Copyright © <2010> Kelly Egan

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

Methods of the Radio class¶ ↑

begin(char frequency, char group, char nodeid)

This function initializes the radios parameters and begins listening for reception.

frequency - The carrier frequency the radio will operate at. Options include:
            RF12_433MHZ, RF12_868MHZ, RF12_915MHZ.  This depends on which radio 
            you use and what country you are operating in. 915Mhz is used in North America.

group - (0-255) The group is actually the sync byte that the radio responds to. Radios set to the same
        group will see messages addressed to that group, while other radios will ignore such 
        messages.

nodeid - (1-31) The identifier of this particular radio. There is nothing stopping to radios
         from having the same id but it may cause confusion in communications. Depending on
         context a Node ID of 0 is either anonymous or broadcast.

available()

Returns true when there is a message waiting to be read. Must be called before
accessing other message data.

message()

The message received as a char[].

length()

Length of the message in bytes/characters.

sender()

Who sent the message. If it is 0 it is considered anonymous.

destination()

Who received the message. This is normally the ID of the receiving radio, but 
if, the message is broadcast it will be 0.

write(destination, message)

Send a message out from the radio. Returns true if successfully transmitted. Note this
does not mean the other radio received the message. 

destination - The ID of the destination node. If 0 considered broadcast.

message - the message to be sent as char[].

write(destination, message, anonymous)

If anonymous is set to true message will be sent as Node 0

anonymous - If set to true the message will be sent anonymously.

Arduino pins connected to RFM12B:¶ ↑

Note most Arduinos and clones run on 5V while the RFM12B runs on 3.3V before connecting an Arduino to the RFM12B be sure and account for this voltage difference.

2 RFM IRQ Interupt pin from RFM12B 10 SPI_SS Chip select. 11 SPI_MOSI Data output from Arduino 12 SPI_MISO Data input from RFM12B 13 SPI_SCK Clock input