Protocols
2WinScada connects to field devices through a channel → device → tag hierarchy. Every protocol page follows the same order: channel definition, device definition and tag definition. The common definition screens are described on the Tag Management page.
| Protocol | Addressing guide |
|---|---|
| Modbus Serial | Modbus Addressing |
| Modbus Serial over Ethernet | Modbus Addressing |
| Modbus TCP | Modbus Addressing |
| Siemens S7 TCP | Siemens S7 Addressing |
| EtherNet/IP | On the protocol page |
| OPC DA Client | On the protocol page |
| MQTT Client | On the protocol page |
| OPC UA Client | On the protocol page |
| MTConnect | On the protocol page |
| BACnet | On the protocol page |
| Database (ODBC) | On the protocol page |
| REST Client | On the protocol page |
| REST Server | On the protocol page |
| Internal (Memory Channel) | No address is used |
Support limits
The following definitions are not supported in 2.10. They cannot be selected in the interface, and the server rejects them on save:
| Protocol | Unsupported definition |
|---|---|
| Modbus (Serial, Serial over Ethernet, TCP) | String data type, a Length greater than 1, an address that does not match the data type (rules) |
| Siemens S7 TCP | LInt, ULInt and LWord; a Bool tag without a bit address, or a non-Bool tag with a bit address (rules) |
| OPC UA Client | Certificate and IssuedToken identities |
| OPC DA Client | A server on a remote computer (local only) |
| BACnet | IPv6 address type; writing to String objects and to objects other than Analog/Binary/Multi-state |
Tags, devices and channels saved with these definitions are not deleted; they show Bad quality and the reason is written to the service log. To fix them, change the definition to a supported value and save. On an OPC DA channel, a saved remote computer name is kept but not used; the channel connects to the local server.
REST Client vs. REST Server
With REST Client, 2WinScada polls the external system for data periodically. With REST Server, IoT devices and external software send the data themselves to the 2WinScada REST endpoint, using a device key.