Rockwell Automation 2755 Enhanced Decoder Series B - Manual (Page 146)

10–11 Configuration: Host Message Replacement Rules
Publication 2755-833
If Scanner A reads the following symbols:
AB1 1AB BA1
Then the host message would be AB1AB1AB1. Since the first
symbol read satisfies the search criteria, it will continue passing
through the rule until all host fields are filled.
Changing the symbol number to 2 would lead to a host message of
1AB1AB1AB.
Instead, if the Symbol Number parameter is set to All and the host
message field number is set to All, then each symbol that has
satisfied a rule is “marked”. That symbol’s marked status prohibits
other rules with both Symbol Number and Host Message Field
Number parameters set to All from using it.
For example, resetting the symbol number to All in the configuration
illustrated above results in a host message of AB11ABBA1.
This occurs because AB1 (the first symbol read) satisfies the rule and
is used for host field one. Since AB1 has now been used, and both
symbol number and host message field number are set to All, AB1
won’t be considered for the second pass through the rule. Instead,
1AB will satisfy the rule on the second pass, and will be used for
host field two and will be marked so it will not be considered for the
third pass. BA1 satisfies the third pass, and will be used for host field
three.
Find String Containing
Field Type Options
Edit Text
Any valid string up to 24
characters in length
Blank
If not blank, enables the selected rule number and specifies a string
for which to search among incoming symbols. The string may
consist of any valid combination of ASCII characters and
metacharacters. All the Find String Containing fields are empty by
default, which disables all host message replacement rules. Only
enabled rules will affect decoder performance. All rules are empty –
and therefore disabled – at default startup.