InfoPrint 5504-R40, Руководство пользователя

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Appendix
Nonvolatile Memory Nonvolatile memory stores variables that must be
preserved when the printer is turned off, such as
configuration parameters and printer usage statistics.
Nonvolatile memory is preserved because RAM is
housed on the controller board, which contains an
independent, battery-operated power supply. When
printer power is turned off, the battery supplies the
power needed to keep stored data active. Nonvolatile
memory also includes storage in disk.
NVRAM Acronym of Nonvolatile Random-Access Memory.
See Nonvolatile Memory.
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.
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 Sensing Use of the lower media sensor only to transmit and
receive infrared light off the underside of media to
detect gaps, notches, holes, or 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).