National Instruments GPIB-PC - Manual (Page 251)

Glossary
©National Instruments Corp. G-3 GPIB-PC User Manual
DMA or DIRECT MEMORY ACCESS - High speed data transfer
between the GPIB-PC and memory that is not handled directly by
the CPU. Not available on some systems. See Programmed I/O.
DRIVER - Common term for software used to manipulate a device or
interface board. See Handler.
END or END MESSAGE - A message that signals the end of a data
string. END is sent by asserting the GPIB End or Identify (EOI) line
with the last data byte.
EOI - A GPIB line that is used to signal either the last byte of a data
message (END) or the parallel poll Identify (IDY) message.
EOS or EOS BYTE - A 7- or 8-bit end-of-string character that is sent as
the last byte of a data message.
GET or GROUP EXECUTE TRIGGER - A GPIB command to trigger a
device or internal function of an addressed Listener.
GPIB or GENERAL PURPOSE INTERFACE BUS - The common name
for the communications interface system defined in IEEE Std 488.
Hewlett-Packard, the inventor of the bus, calls it the HP-IB.
GPIB ADDRESS - The address of a device on the GPIB, composed of a
primary address (MLA and MTA) and perhaps a secondary address
(MSA). The GPIB-PC has both a GPIB address and an I/O address.
GPIB.COM - The GPIB-PC handler filename.
GPIB-PC - The name for the National Instruments family of GPIB
interface boards to personal computers. Family members include
GPIB-PCII, GPIB-PCIIA,GPIB-PCIII, GPIB-PCjr, GPIB-PC2000,
and Rainbow GPIB-PC.
GTL or GO TO LOCAL - A GPIB command used to place an addressed
Listener in local (front panel) control mode.
HANDSHAKE - The mechanism used to transfer bytes from the Source
Handshake function of one device to the Acceptor Handshake
function of another device. The three GPIB lines DAV, NRFD, and
NDAC are used in an interlocked fashion to signal the phases of the
transfer, so that bytes can be sent asynchronously (e.g, without a
clock) at the speed of the slowest device.