Rockwell Automation 5370-OCR2 PAK - Manual (Page 26)

Chapter 4
OCR Tool Configuration
4–7
Match String
In OCV mode, the recognized characters are compared to Match Strings,
and the tool will fail if the strings do not match. If you select the match
string box with OCV mode selected, a keyboard will be displayed, allowing
you to enter a match string.
Metacharacters can be entered with the keyboard or by selecting the
metacharacter buttons at the top of the keyboard. The metacharacter buttons
include:
[A-Za-f] Any alpha
[0-9] Any number
? 0 or 1 occurrences of the preceding character
* 0 or more occurrences of the preceding character
+ 1 or more occurrences of the preceding character
| OR operation
Refer to Chapter 6 for a complete description of match strings and
metacharacters.
Subset
Subset allows you to inspect a portion of a string starting from the left or
right end. The following options are available:
•
All
In this mode, all characters recognized (up to a maximum of 20) are
included in the read string.
•
Left
When Left is selected and more than Len characters are recognized in a
single string, the read string will consist of the left-most Len characters
recognized.
•
Right
When Right is selected and more than Len characters are recognized in a
single string, the read string will consist of the right-most Len characters
recognized.
Note: The maximum number of characters per line = 40. Any characters
over 40 per line are ignored.
Len
Applies to the Left and Right subset options. When a subset of a string is
selected you must enter the length of the subset.