USER'S MANUAL, VERSION 2.0
Copyright © Convergence Systems Limited 2021, All Rights Reserved
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Appendix H: TagFocus
TagFocus is a special Impinj extension to EPC protocol to enable longer persistence time when
Session is S1, Target is Flag A only (no toggle). This combination setting is traditionally used
to inventory a lot of tags. However, since the normal persistence time of this combination as
defined by EPC is only 2 to 5 seconds, so when this time is up, the tag will still go back to Flag
A. Therefore, depending on how many tags the reader can read during this period of 2 to 5
seconds, the inventory will be very fast up to a certain limit and then will become very slow.
For Impinj IC based tags, this TagFocus property, when invoked, will cause the tag to stay in
Flag B a much longer time, until the end of all inventory rounds. This will enable much faster
read when you need to read more than 1000 tags, for example.
