TransCore MPRX, Системное руководство

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MPRX Reader
TransCore Proprietary 7–11
After diagnostics are complete, you may want to reinstate the uniqueness check using
command
#410N Select Unique ID Code Criteria.
Reader response:
Done
410N Select Unique ID Code Criteria (Anti-passback Feature)
Command
#410N
instructs the reader to buffer and transmit ID codes according to the
following test: an ID is read if previously decoded IDs have changed value at least
N
+1
times since the new ID was last received. IDs that do not pass the test are not reported. The
factory-default setting is command
#4100
, which selects a separation of one ID. Variable
N
specifies ID separation as shown in Table 7 – 6.
Table 7 – 6 Unique ID Code Criteria
Each time the reader receives a tag ID, it compares the ID with the contents of a
comparison register. This register contains the following two items:
Item 1 Most recently acquired ID
Item 2 Second-most recently acquired ID
Item 3 Third-most recently acquired ID
Item 4 Fourth-most recently acquired ID
When the uniqueness filter is set to separation of one ID, the newly acquired ID is
transmitted only if it is different from the first item. Separation of two IDs allows transmission
if the new ID is different from Items 1 and 2 in the comparison register. Separation of three
and four IDs transmit the new ID only if it is different from the first three and the first four
items, respectively.
Note: A new ID can fail the filter test and not be transmitted; however, it remains stored
in the comparison register.
The uniqueness test has a time limit as set by command #44N. If an ID is buffered, it will
not be accepted again unless it arrives at the reader more than the timeout value from the
previous arrival or until the receipt of one or more other IDs reset the uniqueness.
Command Uniqueness Criteria
4100 Separation of 1 ID (factory default)
4101 Separation of 2 IDs
4102 Separation of 3 IDs
4103 Separation of 4 IDs