# How to Send Native Mode Commands

You can use the String Command field to send native mode commands to the vision system from the PLC.

Native mode commands are typically sent over telnet (TCP port 23) and string commands are supported differently on various protocols. For more information about further guidance with native mode and string commands, see the In-Sight Vision Suite Application Development Help.

Note: ProfiNET and CC-Link IEFB currently do not support sending string commands from the PLC.