Protocols and Framing

Channels move bytes. Protocols interpret those bytes as operations such as “read holding register 10”.

Device (ModbusDevice / McDevice / S7Device / FinsDevice / HostLinkDevice / EtherNetIpDevice / custom DeviceBase)
        ↓
Session (FrameSession / ModbusClient / McClient / S7Client / FinsClient / HostLinkClient / EtherNetIpClient)
        ↓
Codec (length frame / RTU / MBAP / MC / S7 / FINS / Host Link ASCII / EtherNet/IP CIP)
        ↓
Channel (serial / TCP / UDP / virtual)

Protocol Packages

Assembly	Scenario
Zeus.Protocols.Framing	Vendor-specific [header][length][payload][checksum] frames
Zeus.Protocols.Modbus	Function codes 01-08, 0F, 10, 11, 16, and 17
Zeus.Protocols.Mc	Mitsubishi MC 1E / 3E / 4E, Binary / ASCII, X/Y/M bits and D/W/R/ZR words
Zeus.Protocols.S7	Siemens S7 TCP DB/I/Q/M common scalar types
Zeus.Protocols.Fins	Omron FINS UDP/TCP CIO/WR/HR/AR/DM/EM/TIM-CNT
Zeus.Protocols.HostLink	Omron Host Link ASCII CIO/LR/HR/AR/DM
Zeus.Protocols.EtherNetIp	Allen-Bradley EtherNet/IP CIP tags and attributes

Protocol packages only depend on IChannel, so the same device code can run over serial, TCP, UDP, or virtual responders.

Request and Response

Most industrial buses are request/response and should be serialized per channel. FrameSession, ModbusClient, and other protocol clients handle this internally. If multiple devices share one channel, avoid concurrent direct protocol calls.

See Custom Framing, Modbus, Mitsubishi MC, Siemens S7, Omron FINS, Omron Host Link, and EtherNet/IP.