Glossary
© National Instruments Corp.
G-9
NI-488.2M SRM for OS/2
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 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 OS/2 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.