Glossary
© National Instruments Corp. Glossary-7 NI-488.2 User Manual for Windows
Ss Seconds.
SDC Selected Device Clear is the GPIB command used to reset
internal or device functions of an addressed Listener. See
DCL and IFC.
serial poll The process of polling and reading the status byte of one
device at a time. See parallel poll.
Service Request See SRQ.
source handshake The GPIB interface function that transmits data and
commands. Talkers use this function to send data, and the
Controller uses it to send commands. See acceptor handshake
and handshake .
SPD Serial Poll Disable is the GPIB command used to
(Serial Poll Disable) cancel an SPE command.
SPE Serial Poll Enable is the GPIB command used to
(Serial Poll Enable) enable a specific device to be polled. That device must also be
addressed to talk. See SPD.
SRQ (Service Request) The GPIB line that a device asserts to notify the CIC that the
device needs servicing.
status byte The IEEE 488.2-defined data byte sent by a device when it is
serially polled.
status word See ibsta.
synchronous Refers to the relationship between the NI-488.2 driver
functions and a process when executing driver functions is
predictable; the process is blocked until the driver completes
the function.
System Controller The single designated Controller that can assert control
(become CIC of the GPIB) by sending the Interface Clear
(IFC) message. Other devices can become CIC only by
having control passed to them.