Glossary
© National Instruments Corp.
Glossary-7
NI-488.2M UM for Windows NT
S
s
Seconds.
SDC
The GPIB command used to reset internal or device functions
(Selected Device Clear)
of an addressed Listener. See DCL.
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
The GPIB command used to cancel an SPE command.
(Serial Poll Disable)
SPE
The GPIB command used to enable a specific device to be
(Serial Poll Enable)
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-488.2M 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.