Rules hierarchy (in bar codes), Rules hierarchy (in bar codes) -6 – Symbol Technologies DS 3408 User Manual
Page 238
DS 3408 Product Reference Guide
15-6
and the cashier will key the price manually.
To implement this, first enter an ADF rule that applies to the normal situation, such as:
Scan Rule Belongs to Set 1. When scanning a bar code of length 15, send the next 2 characters, send the class key, send the next
8 characters, send the stock key, send the data that remains, send the Enter key.
The “sale” rule may look like this:
Scan Rule Belongs to Set 2. When scanning a bar code of length 15, send the next 2 characters, send the class key, send the next
8 characters, send the stock key.
To switch between the two sets of rules, a “switching rule” must be programmed. This rule specifies what type of bar code must be
scanned to switch between the rule sets. For example, in the case of the “sale” rule above, the rule programmer wants the cashier
to scan the bar code “M” before a sale. To do this, a rule can be entered as follows:
When scanning a bar code of length 1 that begins with “M”, select rule set number 1.
Another rule could be programmed to switch back.
When scanning a bar code of length 1 that begins with “N”, turn off rule set number 1.
The switching back to normal rules can also be done in the “sale” rule. For example, the rule may look like this:
When scanning a bar code of length 15, send the next 2 characters, send the class key, send the next 8 characters, send the stock
key, turn off rule set 1.
bar code on page 15-10 after programming a rule belonging to an alternate rule
set.
In addition to enabling and disabling rule sets within the rules, enable or disable them by scanning the appropriate bar codes on
.
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 matches (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 to program the most
general rule last.
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 using the standard data editing functions. Scan options are entered as ADF rules,
and the hierarchy mentioned above also applies to them. For the digital scanner, this applies to prefix/suffix programming in the
parameter Scan Data Transmission Format.