EXFO FTB-1v2 Guide De L'utilisateur page 487

Accessing Modules
A session can directly access an instrument using valid LINS commands
such as LINS10:SOURce:DATA:TELecom:CLEar.
However, in a context of multiple sessions, additional commands are
available to inform other sessions that an instrument is currently in use.
When a session uses the CONNECT LINS command, another session using
the same CONNECT LINS command will receive an error indicating that
the instrument is already in use.
For example:
SESSION 1 sends this command:

CONNECT LINS10
The command returns...OK
SESSION 2 sends this command:

CONNECT LINS10
The commands returns...Error
At this moment, SESSION 2 knows that LINS10 is already in use by another
session.
Note: Both sessions must use these commands to ensure that they receive
accurate information.
FTB-1v2 and FTB-1v2 Pro
Communicating Through TCP/IP Over Telnet
Accessing Modules
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