NonStop S-Series Hardware Installation and FastPath Guide (G06.25+)

Glossary
HP NonStop S-Series Hardware Installation and FastPath Guide—529443-001
Glossary-125
wye-delta
phase displacement between each point on the Y is 120 degrees. The center point of
the Y is the common return point for the neutral conductor.
wye-delta. The interconnections between a wye source and a delta load.
X.21. A digital signaling interface recommended by the International Telecommunications
Union, Telecommunication Standardization Sector (ITU-T) that includes specifications
for data terminal equipment/data communications equipment (DTE/DCE) physical
interface elements, alignment of call control characters and error checking, elements of
the call control phase for circuit switched services, data transfer at or below 9600
bits/second, and test loops.
X fabric. The X side of the internal or external ServerNet fabrics. See also fabric, external
ServerNet X or Y fabric, and internal ServerNet X or Y fabric.
XEP table. See external entry-point (XEP) table.
XIO. See extensible input/output (XIO).
XLLink. An Accelerator-related tool invoked by SYSGENR only for TNS/R systems. XLLink
binds together separately accelerated modules of TNS library code to make system
libraries. XLLink preserves and fixes up the existing Accelerator-generated MIPS RISC
code, avoiding the additional time needed for a complete acceleration from TNS
instructions. XLLink is not supported for program files, user libraries, or shared run-
time libraries.
XO bond. The bond connection on an isolation transformer, installed between the
transformer’s neutral XO terminal and ground. This bond is required at North American
and British sites to provide an effective return path for any equipment conductor fault
current back to the neutral of the isolation transformer.
Y fabric. The Y side of the internal or external ServerNet fabrics. See also fabric, external
ServerNet X or Y fabric, and internal ServerNet X or Y fabric.
$YMIOP. The name of the maintenance I/O process that is built during system generation
and is available at system startup.
$ZCNF. The name of the configuration utility process.
zero-signal reference. A connecting point, bus, or conductor used as one side of a signal
circuit. Such a reference object might or might not necessarily be designated as a
ground. Sometimes referred to as a common circuit.
$ZEXP. The name of the Expand manager process.
$ZMnn. The name of the QIO monitor process in processor nn.
$ZNET. The name of the Subsystem Control Point (SCP) management process.