Visara SCON-20L Installation - Manual (Page 91)

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Appendix A. Glossary of Terms
ATL - Automated Tape Library.
Basic Mode - The mode of the mainframe processor when it is not configured for
LPAR mode. Only one partition.
CCW - Channel Command Word. A doubleword at the location in the host’s main
storage identified by the Channel Address Word. CCWs are used to direct data channel
operations.
CHPID - Channel Path Identification. This is a number associated with a communication
path between the host and a controller.
Command Chaining - The fetching of a new CCW immediately following the
completion of the previous CCW.
Console - The term usually used to refer to a Non-SNA terminal that is used to help
manage the operating system or one of the started tasks running on the mainframe.
CNC - A mnemonic used to define an ESCON channel type.
CUADD - The CUADD is a parameter used in ESCON host definitions that refers to
one of 16 logical paths through an ESCON channel. The value is given as a single hex
digit.
CU Image - Another term used to describe how an SCON host circuit appears to
the host. Each CU Image or host circuit appears to the host as if it were a control unit.
CUT - Control Unit Terminal. A Control Unit Terminal is a device that depends on
the SCON to decode keyboard input from the device, to determine what action is
needed. CUTs supported by the SCON include: fixed-function coax display
terminals, ASCII display terminals, and Telnet clients.
DFT - Distributed Function Terminal. A term used to describe a coax terminal that
processes the host data stream itself, rather than depend on the 3270 controller to process
the data stream for it. DFT devices typically do not have access to CUT features provided
by the SCON such as test mode panels, configuration, MLS, etc.
DSL -Down Stream Loadable. The term DSL refers to a special category of IBM
terminals that depend on the controller to download their operating software over a
coax connection. A typical DSL device used for console operations is the IBM 3290
Plasma Display.
EMIF - ESCON Multiple Imaging Facility
ESCD - Enterprise Systems Connection Director (ESCON Director, switch).