Typically, we have a PLC with a serial channel - e.g. RS485 - and a device connected to it, communicating with the Modbus protocol. Devices are, for example, various I/O modules, UI/UC... room controllers, air conditioners, or solar power plant inverters. Domat IDE needs to know what address the device has and which registers specific data is read and written to. Domat IDE includes a pre-installed Domat device library, which can also be detected automatically. But a prototype needs to be created for third-party devices.