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Operating Instructions Chapter 6
CLV 42x bar code scanner
Operation
8 009 981/O078/16-08-2004
©
SICK AG · Division Auto Ident · Germany · All rights reserved
6-19
6.5.4 Show CP-limits
In this mode, the CLV masks certain parts of the scan line so that any limit values defined
for the active evaluation range of the scan line can be checked directly during
parameterization. The restricted active evaluation range shortens the evaluation time for
fast applications, for example, because the evaluation routine needs only take account of
unmasked parts of the scan line. The range is restricted by entering appropriate values for
M
INIMUM
C
ODE
P
OSITION
and M
AXIMUM
C
ODE
P
OSITION
in the C
ODE
P
OSITION
section on the
R
EADING
C
ONFIGURATION
tab or under D
YNAMIC
R
EADING
C
ONFIGURATION
. The CLV does not
output a reading result.
S
HOW
CP-
LIMITS
can be called up via CLV 42
X
, D
EVICE FUNCTIONS
(interactively).
The CLV masks the scan line alternately from the set value for CP
min
and from the set value
for CP
max
. An example is shown in Fig. 6-11 . The switchover is made continuously at
intervals of one second. The part of the scan line that remains active for the reading
procedure is the section between CP
min
and CP
max
.
Example:
Default setting: Evaluation set for the area from CP
min
= 5 to CP
max
= 95.
The CLV masks the line from CP
min
= 5 (short scan line) and from CP
max
= 95 (long scan
line).
Proceed as follows to check the restricted evaluation range:
1. In the menu bar, choose S
HOW
CP-
LIMITS
under CLV 42
X
, D
EVICE FUNCTIONS
.
The "Device Ready" LED is extinguished. The CLV cancels reading mode and masks the
scan line alternately (as described above) from CP
min
and CP
max
.
2. Check whether the bar code is located centrally in the area between the end of the
shorter scan line (CP
min
) and the end of the longer scan line (CP
max
) or, if there are
several bar codes, to determine whether the center of the field of all the codes is within
range.
3. If necessary, correct CP
min
and CP
max
accordingly. Perform a download to the CLV!
4. In the menu bar, choose R
EADING MODE
under V
IEW
to exit the S
HOW
CP-
LIMITS
mode.
The CLV returns to R
EADING
mode. The "Device Ready" LED lights up.
Note In the reading mode, the CLV does not actually mask the scan line visually, but instead takes
the values specified for the restricted evaluation range into account when the data contents
are decoded.
Fig. 6-7: Appearance of scan line in the "Show CP-limits" mode
CP
max
CP
min
Scan line 2
Scan line 1
"Show CP-limits"
Active area