Rockwell Automation 5370-OCR2 PAK - Manual (Page 63)

A–B
6
Chapter
6–1
Using Match Strings
This chapter describes:
•
Match string usage
•
Metacharacters
•
Testing match strings
•
Example match strings
Important:
This chapter describes match strings of OCR Tools. These match strings
often contain spaces, they are represented by a square character:
h
Match strings are displayed in the OCR Tool Edit panel and on the
string-entry keyboard delimited by arrows at the left and right ends.
Spaces are displayed on the CVIM2 screen as actual spaces rather than as the
character shown above.
When Optical Character Verification (OCV or OCV Strict) mode is selected
for a given string, the OCR Tool compares the read text to a user-specified
match string. Match strings can be used in the following ways:
•
Verify that the read text matches exactly
If no metacharacters are used, the text read by the OCR Tool must match
the match string exactly.
•
Allow extra characters at the beginning or end
Metacharacters can be used to allow the tool to pass if extra characters
appear before or after the desired text.
•
Verify that the read text matches one of several valid sequences
This can be used, for example, to verify that a 3-letter code represents a
valid month of the year.
•
Verify that a particular type of character appears in a certain position
Metacharacters can be used, for example, to specify that a string must
consist of three digits followed by three letters.
Chapter Objectives
Match String Usage