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Newly Optimized RF24Network Layer v1.0.18
2020 - Optimized RF24 Network Layer for NRF24L01 radios
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An overview of addressing in RF24Network
The nrf24 radio modules typically use a 40-bit address format, requiring 5-bytes of storage space per address, and allowing a wide array of addresses to be utilized. In addition, the radios are limited to direct communication with 6 other nodes while using the Enhanced-Shock-Burst (ESB) functionality of the radios.
RF24Network uses a simple method of data compression to store the addresses using only 2 bytes, in a format designed to represent the network topology in an intuitive way. See the Topology and Overview page for more info regarding topology.
Say we want to designate a logical address to a node, using a tree topology as defined by the manufacturer. In the simplest format, we could assign the first node the address of 1, the second 2, and so on. Since a single node can only connect to 6 other nodes (1 parent and 5 children) subnets need to be created if using more than 6 nodes. In this case, the
The above example is exactly how RF24Network manages the addresses, but they are represented in Octal format.
| Decimal | Octal | Binary |
|---|---|---|
| 1 | 01 | 00000001 |
| 11 | 013 | 00001011 |
| 9 | 011 | 00001001 |
| 73 | 0111 | 01001001 |
| 111 | 0157 | 01101111 |
Since the numbers 0-7 can be represented in exactly three bits, each digit is represented by exactly 3 bits when viewed in octal format. This allows a very simple method of managing addresses via masking and bit shifting.
When using Arduino devices, octal addresses can be printed in the following manner:
Printf can also be used, if enabled, or if using linux/RPi
1.9.6