download. Totransfer data from one computer for use
on another one. Typically,users download to a printer,
from a larger computer to a diskette or fixed disk on a
smaller computer,or from a system unit to an adapter.
downloaded fully described fonts. The IPDS form of
host fonts downloaded to a printer.PSF converts pairs
of host font character sets and code pages into IPDS
form before downloading to the printer for printing.
DPE. See Decompression Performance Enhancement
feature.
DPF. SeeDistributed Print Function.
drain. An operator action to halt the flow of jobs to a
printer,usually to stop the printer or to change print
options.
duplex printing. Printing on both sides of a sheet of
paper.Contrast with simplex printing. See also normal
duplex printing and tumble duplex printing.
E
EBCDIC. Extended binary-coded decimal interchange
code.
electronic overlay. Acollection of constant data, such
as lines, shading, text, boxes, or logos, that is
electronically composed in the host processor and
stored in a library,and that can be merged with variable
data during printing. Contrast with page segment. See
also page overlay and medium overlay.
Enterprise System Connection. See ESCON
channel.
ESA. Enterprise System Architecture.
ESCON channel. Achannel having an Enterprise
Systems Connection channel-to-control unit I/O interface
that uses serial-by-bit optical cable as a transmission
medium.
exception. Acondition that exists when the printer:
vDetects an invalid or unsupported command, order,
control, or parameter value from the host.
vFinds a condition requiring host-system notification.
vDetects a condition that requires the host system to
resend data.
exception highlighting. The markings placed on the
printed page to indicate the source of a data stream
error.Two types of highlight markings are used:
vPrint-error marker: a solid rectangle.
vPrint-error vector: a line drawn from a printed error
code to the point on the page where the error
occurred.
extended binary-coded decimal interchange code
(EBCDIC). Acoded character set of 256 eight-bit
characters.
F
FCB. See forms control buffer.
FGID. See font global identifier.
file.
vIn PSF for OS/2, a collection of related data.
vIn PSF for OS/390, a member of a partitioned data
set or a sequential data set.
vIn PSF/VM, a CMS file.
vIn PSF/VSE, a member in a library.sublibrary.
fixed metrics. Measurement information in specific
units such as pels, inches, or centimeters for individual
or collections of graphic characters. See also font
metrics.
fold memory. Theability of a form to refold at the fold
perforation after exposure to heat during the fusing
process.
font. (1)A family or assortment of characters of a
given size and style; for example, 9 point Bodoni
Modern. (A). (2) One size and one typeface in a
particular type family,including letters, numerals,
punctuation marks, special characters, and ligatures. (3)
Apaired character set and code page that can be used
together for printing a string of text characters.A
double-byte font can consist of multiple pairs of
character sets and code pages. (4) See coded font,
double-byte coded font, and symbol set..
font character set. Synonym for character set.
font global identifier. (1)A number that identifies the
character style and size for certain printers. (2)A unique
value that identifies the type family,typeface, and,
sometimes, the point size of a character set.
font metrics. Measurement information that defines
individual character values, such as height, width, and
space, as well as overall font values, such as averages
and maximums. Font metrics may be expressed in
specified fixed units, such as pels, or in relative units
that are independent of both the resolution and size of
the font.
font pruning. An action in which PSF reduces the
number of characters downloaded to the printer by
sending only those characters in a character set that
are actually referenced by the code page. Font pruning
can save time needed to download the characters and
can reduce the amount of raster pattern storage used
by the printer but can increase processor use.
font width. (1)A characteristic value, parallel to the
character baseline, that represents the size of all
graphic characters in a font. (2) In a font character set,
nominal font width is a font-designer defined value
corresponding to the nominal character increment for a
font character set. The value is generally the width of
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