CANome is a library that assists you in writing your own CAN based, fully distributed, smart home system.

A bus system provides many benefits over other system. Some of them are listed below:
- **Energy Efficiency:** Each device only needs to implement the fairly lightweight CAN stack. The bus cable can also transport the required power for the nodes, reducing the numbers of AC-DC-adapters.
- **Reliability:** A distributed system can handle the loss of nodes without impacting the complete system. Additionally, a wired channel is typically more reliable than a wireless one.
- **Security:** Embedded security is hard, using a bus doesn't make your application more secure, but you have a greatly reduced attack surface: An attacker needs physical access to your bus to even start to communicate with a node.

Many other smart home projects use a meta-configuration-language to configure the firmware on each device.
A distributed system requires more logic on the nodes than a centralized one.
A meta-configuration-language will always have missing features that are a core component of a regular programming language, like rust.

This project helps you in creating a distributed smart home system in rust by providing a library with the building blocks.
You express the entire node logic as regular embedded rust code using this library to avoid writing extensive repeating code.

# Protocol
This project uses a very simple protocol that is based on CAN.
Each node can expose states.
A state is a Rust type that can be encoded/decoded from a CAN frame.
The format of a frame is implicitly transmitted by the CAN message identifier.
When a state changes, the node broadcasts the new state on the bus.

Other nodes can "subscribe" to a CAN message identifier.
They always store a copy of the state that is automatically updated when a new message with that CAN message identifier arrives.
Additionally, a node can use a CAN remote frame to fetch the state from the source node.

# Contributing
I'm happy about any contribution in any form.
Feel free to submit feature requests and bug reports using a GitHub Issue.
PR's are also appreciated.

# License
The Sourcecode in this Library is licensed under [LGPLv3](https://www.gnu.org/licenses/lgpl-3.0.en.html).