User Guide

Table Of Contents
Multi-Protocol Tag Commands
54
Get Tag EPCs and Metadata
Using this syntax for getting information from the tag buffer provides several benefits:
When at tag EPC is returned there is no padding if the actual tag EPC is shorter than
the configured max EPC length. This helps minimize the amount of data returned.
Any or all fields of the Tag Read Meta Data can be returned.
In the event of a communication error the last Get EPC and Metadata request can be
repeated.
When data is requested using this syntax the response will contain as many tags as can
be fit in the response packet. The response will indicate how many tags were returned
and should be processed accordingly.
This version of Get Tag Buffer takes two additional fields: the Metadata Flags which
defines what metadata will be returned and the Read Options which specifies special
read functionality. The following table lists the supported values for these fields.
Get EPC and Metadata Request Fields
Field Value Description
Metadata Flags
(to specify more
than one OR
the values
together)
0x0000 When no flags are set no meta data will be returned, only the tag
EPC (including PC bits and tag CRC)
0x0001 When bit 0 is set the Read Count will be returned
0x0002 When bit 1 is set the LQI/RSSI will be returned
0x0004 When bit 2 is set the Antenna ID will be returned
0x0008 When bit 3 is set the Frequency will be returned
0x0010 When bit 4 is set the Timestamp will be returned
0x0020 RFU (ThingMagic Only)
0x0040
When bit 6 is set the Protocol ID, as defined by the Tag Protocol
IDs table, will be returned