Speedway Reader IPJ-R1000 for UHF Gen 2 RFID
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Successive Selects
may apply to different memory banks. The Bit
Offset and Bit
Length fields are used to target a specific
portion of the tag memory on which to perform the filtering, while the Pattern field contains the comparison bits of interest.
Note that the Bit Length must be non-zero. As tags are read, the Pattern is evaluated against the Select criteria, which includes
Equal
and Not
Equal
options in the Comparison field.
The Inventory
Filter allows the use of two sets of criteria (defined by primary filter A and secondary filter B) that may be used
separately, jointly, or not at all (the pull-down options include No Filter, A ONLY, A AND B, A OR B). When applied to an
inventory round, only those tags that match the Select criteria will be displayed.
Figure 6-3 Inventory Filter
In Figure 6-3, the Pattern written is “0xE017FF00431E55550000000000000000, the bit offset is “0x0020”, and the bit length is
“0x0040.” The bit offset for an EPC code must be nonzero because the first 32 bits in the memory map (see Figure 6-4) are
taken up by the CRC and PC codes. Figure 6-5 provides an example of how this pattern would be stored into the tag memory.
