Omron V500-R521B2 User Manual page 123

Section 6
Appendix
PCS
PCS is an abbreviation of "Print Contrast Signal" and is a value of reflectance ratio of
space (ground color) and a bar indicated in a calculation formula.
PCS can be calculated by the following formula.
The PCS of this bar code reader is 0.45 or more. (However, ground color reflection
ratio is 85 %.)
When expressing PCS, the above formula only may be a relative value. Ground color
(space) reflection ratio condition is required to specify to recognize as an absolute value.
MRD
MRD is an abbreviation of "Minimum Reflectance Difference", indicating contrast of
bars and spaces. MRD can be calculated by the following formula.
The MRD of this bar code reader is 32 % or more. (However, ground color reflection
ratio is 85 % or more.)
RS/CS control
Control system to communicate data between the bar code reader and the upper
equipment. Data is transmitted while verifying to hardware through RS/CS line
"whether to transmit or not".
EAN128 (Reading specification)
The head of EAN128 data always starts with "Start code" + "FNC1".
Start
Code
EAN start pattern
When "Only EAN128 reading is allowed (G6)" is set, codes other than this combination
may be read error.
When "All reading allowed including EAN (G5)" is set, CODE128 other than this
combination can be read.
Start pattern of EAN128 is converted to "C1" (5Dh43h31h in ASCII code) and output.
"FNC1" (separator) indicating data separation is converted to "GS" and output.
V500-R521B2/C2
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User's Manual
RL - RD
PCS =
RL
• RD: Reflection ratio of a bar
• RL: Reflection ratio of ground color (space)
MRD = RL - RD
• RD: Reflection ratio of a bar
• RL: Reflection ratio of ground color (space)
Data 1 Data 2
Fixed Variable
FNC1
length length
Data 3
Check
Variable
FNC1
digit
length
Separator
Stop code