Rules hierarchy (in bar codes), Rules hierarchy (in bar codes) -4 – Motorola LS3578 User Manual

Page 226

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12 - 4 Symbol LS3578 Product Reference Guide

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.

For optimal results, scan the

Disable All Rule Sets

bar code on

page 12-7

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

page 12-7

.

Rules Hierarchy (in Bar Codes)

The order of programming individual rules is important.The most general rule should be programmed first.

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.

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