Home Assistant Add-on: Rehau Neasmart 2.0 Gateway

This Add-On is used to provide a shim between the Rehau Neasmart 2.0 SysBus interface (glorified Modbus) and Homeassistant through a set of REST APIs

This Add-On was built to be used in conjunction with a custom integration to expose the Rehau Neasmart 2.0 system as a climate entity

This Add-On supports persistent storage (static size at around 3M) for registers state storage

How to use

Configure your Serial to USB adapter or a ModbusRTU Slave to ModbusTCP adapter. Here's the how-to for the waveshare RS485 TO POE ETH (B)
Install the addon by adding this addon repository to you homeassistant installation
Configure the addon specifying the Serial port path or listening address in the listening_address field, configure a listening_port matching the ModbusRTU Slave to ModbusTCP adapter configuration
Configure whether to use tcp or serial as server_type (if you have specified a Serial port in the listening address you'll need to use serial)
Configure a slave_id valid ids are 240 and 241. This addon can co-exist with the KNX GW albeit a different ID

The addon on first startup will init an empty database so all write regs will be zeroed, a change on write regs is required to start showing those values in reading
If the addon is down and a change happens through other means (eg. app, thermostat) the register won't be updated and on addon restart the old value will be re-read through the bus and the change will be invalidated
SQLITE is not the best for very slow disks, network disk (if missing flock()) and SD Cards (writes happening at every registers update can kill them)
Flask development server
API Auth & Ingress