Symbol LS3478-ER, Справочное руководство

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Symbol LS3478 Product Reference Guide 14-6
Rules Hierarchy (in Bar Codes)
The order of programming individual rules is important.The most general rule should be programmed last.
All programmed rules are stored in a buffer. As they are programmed, they are stored at the “top” of a rules list. If three rules have
been created, the list would be configured as follows:
Third Rule
Second Rule
First Rule
When data is scanned, the rules list is checked from top to bottom to determine if the criteria match (and therefore, if the actions
should occur). Input is modified into the data format specified by the first matching set of criteria it finds. Be sure that the most general
rule is the last one programmed.
For example, if the THIRD rule states:
When scanning a bar code of any length, send all data, then send the ENTER key.
And the SECOND rule states:
When scanning a Code 128 bar code of length 12, send the first four characters, then send the ENTER key, then send all remaining
data.
If a Code 128 bar code of length 12 were scanned, the THIRD rule would be in effect. The SECOND rule would appear to not function.
Note also that ADF rules are actually created when the standard data editing functions are used. Scan options are entered as ADF
rules, and the hierarchy mentioned previously also applies to them. For the scanner, this applies to prefix/suffix programming in the
parameter
Scan Data Transmission Format .
These rules reside in the same “rule list” as ADF Rules, so the order of their creation is also important.
Default Rules
Every unit has a default rule to send all scan data. Units with custom software may have one or more default rules burned in. The
rules hierarchy checks user programmable rules first, then the default rules. Default rules can be disabled by entering the following
general rule in the user programmable buffer:
When receiving scan data, send all data.
Since this rule always applies, ADF never goes into the default rules.
Special Considerations for Multipoint Networks
ADF rules scanned by an individual scanner are NOT broadcast to other scanners in the piconet, as are other parameters; however,
ADF rules that 123Scan generates ARE broadcast to all scanners in the piconet. 123Scan rules transmitted from the base are stored
at the BEGINNING of the ADF rule buffer, regardless of the presence of existing rules, while rules scanned by the scanner are
appended to the existing buffer. For this reason, transmit rules to be shared by all scanners from 123Scan FIRST. Then, scan rules to
customize an individual scanner after 123Scan rules are transferred.