Interpreting Scan Codes As Binary Format By The Scanning Software - Pitney Bowes FastPac DI900 Manuallines

DI900/DI950
Scan Codes
and Levels
✍
TIP: See Appendix A,
Base Code Theory for
more information on
number bases.
✍
TIP: See Chapter 3,
Barcode Theory for
more information on
how barcodes work
and are programmed.
✍
TIP: In the Scan Code
Specification Sum-
mary tables on the
preceding pages, the
column "How Mark is
Detected" lists how
that mark function is
activated (by mark
presence, absence, or
either method).
SV61314 Rev. A
DI900/DI950 Scan Code Concepts • 2
Interpreting Scan Codes as Binary Format by Scanning Software
Part of the scanning process involves converting scan code marks into ASCII
text and storing it in a binary format. Binary format (or base 2), is the sim-
plest numbering system possible and has just two numbers (or states), "0"
(or OFF), and "1" (ON). It is used in software to process raw information (like
scan marks) into something usable in an application (in this case, to run a job
on an inserter).
For OMR scanning, each mark (referred to as a "bit" when scanned) is con-
verted into binary bits. When a mark is scanned, it is read as a "1"; and if no
mark is scanned (when there is mark position designated), it is read as a "0".
Because there is no other way to represent OMR marks digitally, the counting
system (code base) for OMR symbology must also be binary. This has impli-
cations when multi-mark functions are used [see "Multi-Bit (Mark) Functions"
on next page].
For barcode scanning, each "byte" (character) of a barcode (up to 12 for Code
39) is converted into binary data. A byte, however, can contain up to 5 "bits"
of information, with each bit representing a specific scan function. Also, when
a byte (or bit) is read, the software can store the binary information in different
code bases (as set up in the scan definition on the inserter). Consequently,
because there are more bits available in a barcode than in OMR, and more
(i.e., larger) code bases from which to choose, the counting system available
for barcode is much higher than with OMR symbology. This again has implica-
tions when multi-bit functions are used [see "Multi-Bit (Mark) Functions" on
next page].
Presence and Absence for Scan Mark Function Activation
Because the scan marks are scanned as ASCII binary text, logically, a "0"
would represent a mark that is not seen (while scanning OMR marks) or a
function turned off in a particular bit (when scanning barcodes). Conversely,
a "1" would represent a mark that is seen (while scanning OMR marks) or a
function turned on in particular bit (when scanning barcodes). The software
in the DI900/DI950 does work like this, but it also has the capability for cer-
tain scan functions to interpret marks in "reverse"; that is, when no mark is
scanned (or a "0" found in the bit of a barcode), a feature is activated.
Consequently, the possible choices for DI900/DI950 scan code designations
for marks (or functions) are:
Presence – The scanning presence of a mark will activate this function.
Absence – The scanning absence of a mark will activate this function.
Presence or Absence – You have a choice of using presence or absence
of a mark to activate this function.
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