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Appendix D
Parity (check)
Parity checking is the addition of a non-data bit to
data, resulting in the number of “1 bits” being either
always even or always odd. Parity is used to detect
transmission errors. Parity represents value in the
check digit of the received or transmitted data.
PCBA
Printed Circuit Board Assembly. A PCB with
components (ICs, resistors, capacitors, etc.)
installed.
Port
A data channel used for receiving data from or
transmitting data to one or more external devices.
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.
Quick Change Memory Cartridge (QCMC)
This cartridge provides a way to easily copy a
printer’s firmware and configuration settings from one
printer to another. A “snapshot image” of the source
printer is stored onto the QCMC and a simple
interface is provided to copy that image to a target
printer.
RAM
Random-Access Memory. Also called “main
memory” or “working memory.” It is the active
memory of the printer into which programs are
loaded. RAM is saved to volatile memory because
data in RAM is lost when power is turned off or
interrupted.
Reflective Mark Sensing
Use of the media sensor to transmit and receive
infrared light off the underside of media to detect
horizontal black marks used for determining the Top-
of-Form position on labels or for indicating a Paper
Out condition.
Resolution
A measure expressing the number of component
units in a given range used to create an image; in
printing, expressed as the number of dots per inch
(dpi) horizontally and vertically.
RFID Encoder
The RFID (Radio Frequency Identification) encoder
programs smart labels (tags with embedded inlays).
Roll Media
Media supplied in a roll format, on a 3-inch cardboard
core.
