Socket Interface
The controller can use socket interfaces to communicate with Ethernet devices that do not support the
EtherNet/IP™
application protocol. The socket interface is implemented via the socket object. The controller communicates with the socket object via MSG instructions. MSG instructions that configure and operate the socket interface must be configured as Unconnected and use the Message to Self path. To communicate with another device, you must understand the application protocol of the other device.
IMPORTANT:
Keep these in mind when you use sockets with the controllers:
- Use unconnected MSG instructions for socket servers. When you configure a MSG instruction, make sure that the Connected checkbox on the Message Configuration dialog box is cleared.
- When a controller operates in Dual-IP mode and uses a socket object, you can use an IP address with a Socket_Create service type.
These devices support as many as 32 socket instances each:
- Controllers, firmware revision 35.011 or later
- 1756-EN4TR modules, firmware revision 5.001 or later
For more information on the socket interface, see the EtherNet/IP Socket Interface Application Technique, publication ENET-AT002.
TLS Support
The secure socket option adds support for Transport Layer Security (TLS) to the socket object.
HTTP(S) REST API Client Support
You can develop your application to send HTTP REST API requests and implement HTTPS via the socket interface with TLS. For more information, see the documentation for these objects in the Common Application Library available from the Product Compatibility and Download Center at rok.auto/pcdc:
- raC_Impl_HTTPClient
- raC_Impl_HTTPCmdGET
- raC_Impl_HTTPCmdPOST
- raC_Impl_HTTPCmdPUT
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