IBM 6500 User Manual page 305

pitch. The number of text characters printed per
horizontal inch. Specified in characters per inch or cpi.
pixel. Derived from picture (PIX) ELement. The
smallest displayable picture element on a video
monitor or printable unit. In printing, a pixel is a dot.
PMPP. Physical Maximum Print Position. The longest
line the printer is capable of printing. This differs from
MPP in that the printer may be capable of printing
lines 132 characters wide (PMPP), but the print job is
only 80 characters wide (MPP). See also MPP.
point. A unit of length in printing and typography,
used to specify type sizes, heights of font characters,
and so forth. There are 72 points in a vertical inch;
thus, one point equals 1/ 72 inch, or approximately
0.0139 inch.
POR. Power On Reset.
port. A channel used for receiving data from or
transmitting data to one or more external devices.
portrait. Printed parallel to the paper motion.
print mode. Font.
proportion, character. See character proportion.
proportional. See font, proportional.
protocol. The rules and conventions that govern
communication between a printer and a host computer.
A protocol includes codes for printing text and graphics
and codes instructing the printer to perform special
operations. See also compatibility and emulation.
R
RAM. Random Access Memory. Can be read from or
written to at any time. RAM is volatile; whatever
information is in RAM is lost when power is removed
or interrupted.
RD. Receive Data.
read. To retrieve data from memory or from mass
storage (hard disk, floppy diskette, and so forth).
Ready mode. Online. The printer is ready to receive
and process commands and data.
reset. To turn off, deactivate, disable, or return to a
previously determined state.
resolution. A measure expressing the number of
component units in a given range used to create an
image in print. Expressed as the number of dots per
inch (dpi) horizontally and vertically.
ROM. Read Only Memory. Programs, instructions,
and routines permanently stored in the printer that
cannot be written to. Information in ROM is not lost
when power is turned off. (ROM-resident fonts are
fonts permanently stored in a printer and available at
any time via software commands to the printer.)
Roman. An NLQ type style in which the characters
are upright and the edges of the characters have a serif.
This sentence is printed in a Roman type style.
RTS. Request To Send.
S
SA. Set Attribute.
SAA. Systems Application Architecture.
sans serif. An NLQ type style in which the characters
are upright and blocked. This sentence is printed in a
sans serif type style.
SCS. System Network Architecture (SNA) Character
String. Usually commands to set printer format, and so
forth.
serial communication. The sequential transmission of
data, in which each element is transferred in
succession.
set. To turn on, activate, invoke, or enable.
SFCC sequence. Special Function Control Character
sequence. Two or more bytes that describe a specific
printer control function. The first byte is always the
SFCC. This also applies to IGP options.
shuttle. The subassembly in a line matrix printer that
includes the hammer bank assembly, plus some or all
of the drive mechanism.
size, type. See point.
SLD. Set Line Density.
slew. Rapid vertical paper movement.
SNA. Systems Network Architecture.
SOH. Start Of Header.
spacing. See font, proportional and font, monospaced.
SSCC. SuperSet Control Character. See escape
sequence and command sequence.
start bits. In serial data transfer, a signal indicating the
beginning of a character or data element.
stop bits. In serial data transfer, a signal indicating the
end of a character or data element.
string. Two or more bytes of data or code treated as a
unit.
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Glossary