Tag read meta data – ThingMagic Micro Hardware User Manual
Page 66
Tag Read Meta Data
A D I V I S I O N O F T R I M B L E
Functionality of the Micro
61
Tag Read Meta Data
In addition to the tag EPC ID resulting from Micro inventory operation each
TagReadData (see MercuryAPI for code details) contains meta data about how, where
and when the tag was read. The specific meta data available for each tag read is as
follows:
Meta Data Field
Description
Antenna ID
The antenna on with the tag was read. If the same tag is read
on more than one antenna there will be a tag buffer entry for
each antenna on which the tag was read. When
, if appropriately configured, the Antenna ID entry will
contain the logical antenna port of the tag read.
Read Count
The number of times the tag was read on [Antenna ID].
Timestamp
The time the tag was read, relative to the time the command to
read was issued, in milliseconds. If the Tag Read Meta Data is
not retrieved from the Tag Buffer between read commands
there will be no way to distinguish order of tags read with dif-
ferent read command invocations.
Tag Data
When reading an embedded
TagOp is specified for a Read-
Plan the TagReadData will contain the first 128 words of data
returned for each tag.
Note:
Tags with the same TagID but different Tag Data
can be considered unique and each get a Tag
Buffer entry if set in the reader configuration
parameter
/reader/tagReadData/
uniqueByData. By default it is not.
Frequency
The frequency on which the tag was read
Tag Phase
Average phase of tag response in degrees (0
°
-180
°
)
LQI/RSSI
The receive signal strength of the tag response in dBm.
GPIO Status
The signal status (High or Low) of all GPIO pins when tag was
read.