2606B System SourceMeter® Instrument Reference Manual
Appendix C: LAN concepts and settings
2606B-901-01 Rev. B / May 2018
C-9
The following table displays the remote interface protocols supported by the 2606B and their
assigned port numbers.
Port number
Command interface
Port number
Raw socket
5025
Telnet
23
VXI-11
1024
DST (dead socket termination)
5030
Selecting a LAN interface protocol
This section provides details about how to select a remote interface protocol to connect to the 2606B.
The 2606B provides three LAN interfaces with three associated LAN protocols (each interface uses a
different protocol). Select the interface based on the protocol needed. The dead socket termination
interface (DST) is provided to solve connection problems; it is not a protocol choice.
VXI-11 connection
This remote interface is similar to GPIB and supports message boundaries, serial poll, and service
requests (SRQs). A VXI-11 driver or NI-VISA
TM
software is required. Test Script Builder (TSB) uses
NI-VISA and can be used with the VXI-11 interface. You can expect a slower connection with this
protocol.
Raw socket connection
All Keithley instruments that have LAN connections support raw socket communication. This means
that you can connect to the TCP/IP port on the instrument and send and receive commands. A
programmer can easily communicate with the instrument using Winsock on Windows computers or
Berkley sockets on Linux or Apple computers.
Raw socket is a basic ethernet connection that communicates in a manner similar to RS-232 without
explicit message boundaries. The instrument always terminates messages with a line feed, but
because binary data may include bytes that resemble line-feed characters, it may be difficult to
distinguish between data and line-feed characters.
Use raw socket as an alternative to VXI-11. Raw socket offers a faster connection than VXI-11.
However, raw socket does not support explicit message boundaries, serial poll, and service requests.
Dead socket connection
The dead socket termination (DST) port is used to terminate all existing ethernet connections. A dead
socket is a socket that is held open by the instrument because it has not been properly closed. This
most often happens when the host computer is turned off or restarted without first closing the socket.
This port cannot be used for command and control functions.
Use the dead socket termination port to manually disconnect a dead session on any open socket. All
existing ethernet connections will be terminated and closed when the connection to the dead socket
termination port is closed.