CSL CS468 - Slot -Count Parameter Qand Dwell Time (C# and Java Demo App )

CSL CS468 16-Port EPC CLASS 1 GEN 2 RFID READER
USER'S MANUAL, VERSION 2.0.1
Copyright © Convergence Systems Limited, All Rights Reserved
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7.12 Slot-Count Parameter Q and Dwell Time (C# and Java Demo
App)
RFID Protocol Inventory - Query Command contains a Slot-Counter Parameter Q.
When participating Tags receive a Query, they pick a pseudo-random value in the range (0, -1)
and load this value into their slot counter. Tag which picks a zero transition to the reply state
replies immediately. Tags which pick a nonzero value transition to the arbitrate state await a
QueryAdjust or a QueryRep command to decrement the value in its slot counter. Tags reply when
the value in their slot counter (i.e. their slot) is zero. Since Q is an integer in the range (0, 15), the
corresponding Tag-response probabilities range from = 1 to = 0.0000305.
It is usually recommended to set a Q-value that have the corresponding number of slots larger
than the exact maximum number of Tags to be read by the reader. For example, if there are 40
tags to be read by the reader, the Q-value is configured to 6, in which = = 64 > 40.