Glossary - 2 MC75 User Guide

Bar Width. Thickness of a bar measured from the edge closest to the symbol start character to the trail ing edge of the same
bar.
BIOS. Basic Input Output System. A collection of ROM-based code with a standard API us ed to interface with standard PC
hardware.
Bit. Binary digit. One bit is the basic unit of binary information . Generally, eight consecutive bits compose one byte of data.
The pattern of 0 and 1 values within the byte determines its meaning.
Bits per Second (bps). Bits transmitted or received.
BOOTP. A protocol for remote booting of diskless devices. Assigns an IP add ress to a machine and may specify a boot file.
The client sends a bootp request as a broadcast to the bootp server port (67) and the bootp server responds using the
bootp client port (68). The bootp server must have a table of all devices, associated MAC addresses and IP addre sses.
boot or boot-up
The process a computer goes through when it starts. During boot-up, the compute r can run self-diagnostic tests and
configure hardware and software.
bps. See Bits Per Second.
Byte. On an addressable boundary, eight adjacent binary digits (0 and 1) combi ned in a pattern to represent a specific
character or numeric value. Bits are numbered from the right, 0 through 7, with bit 0 the low-order bit. One byte in
memory is used to store one ASCII character.
C
CDMA. Code Division Multiple Access (CDMA) is a form of multiplexing and a method of multiple acc ess that does not
divide up the channel by time (as in TDMA), or frequency (as in FDMA), b ut instead encodes data with a special code
associated with each channel and uses the constructive interference properti es of the special codes to perform the
multiplexing.
CDRH. Center for Devices and Radiological Health. A federal agency responsib le for regulating laser product safety. This
agency specifies various laser operation classes based on power out put during operation.
CDRH Class 1. This is the lowest power CDRH laser classification. This class is considered intrinsi cally safe, even if all laser
output were directed into the eye's pupil. There are no special operating procedures for this class.
CDRH Class 2. No additional software mechanisms are needed to conform to this limit . Laser operation in this class poses
no danger for unintentional direct human exposure.
Character. A pattern of bars and spaces which either directly represents data or indic ates a control function, such as a
number, letter, punctuation mark, or communications control contained in a message.
Character Set. Those characters available for encoding in a particular bar code sym bology.
Check Digit. A digit used to verify a correct symbol decode. The scanner inse rts the decoded data into an arithmetic formula
and checks that the resulting number matches the encoded check digit. Che ck digits are required for UPC but are
optional for other symbologies. Using check digits decreases the chance of substitution errors when a symbol is
decoded.