Motorola MC21XX SERIES User Manual page 104

Glossary - 2 MC21XX Series User Guide
B
Bar. The dark element in a printed bar code symbol.
Bar Code. A pattern of variable-width bars and spaces which represents numeric or alphanumeric data in
machine-readable form. The general format of a bar code symbol consists of a leading margin, start character, data
or message character, check character (if any), stop character, and trailing margin. Within this framework, each
recognizable symbology uses its own unique format. See Symbology.
Bar Code Density. The number of characters represented per unit of measurement (e.g., characters per inch).
Bar Height. The dimension of a bar measured perpendicular to the bar width.
Bar Width. Thickness of a bar measured from the edge closest to the symbol start character to the trailing edge of the
same bar.
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.
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.
bps. See Bits Per Second.
Byte. On an addressable boundary, eight adjacent binary digits (0 and 1) combined 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.
boot or boot-up. The process a computer goes through when it starts. During boot-up, the computer can run
self-diagnostic tests and configure hardware and software.
C
CDRH. Center for Devices and Radiological Health. A federal agency responsible for regulating laser product safety.
This agency specifies various laser operation classes based on power output during operation.
CDRH Class 1. This is the lowest power CDRH laser classification. This class is considered intrinsically 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 indicates 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 symbology.
Check Digit. A digit used to verify a correct symbol decode. The scanner inserts the decoded data into an arithmetic
formula and checks that the resulting number matches the encoded check digit. Check digits are required for UPC