Read tag data (28h), Read tag, Data (28h) – ThingMagic M5e-Compact User Manual
Page 107
Application Tag Commands
Command Set
107
Read Tag Data (28h)
For the deprecated version of this command see Appendix D:
.
The Read Tag Data command reads the specified memory bank at data address location
within that memory bank of a tag. The tag which will be read can be specified using the
or, if Option=0x00 of the Tag Singulation Fields is specified, it will
attempt to read from the first tag it finds. If no tag is in the field, the memory location
doesn’t exist or is read locked, or the Select criteria cannot be satisfied a fault code is
returned.
In addition to the Tag Singulation Fields the Read Tag Data command takes several fields
which specify the data which will be read from the tag. These fields are:
Read Tag Data Fields
The Basic syntax which returns only the requested Tag Data is defined in
.
With additional Option bits set, Read Tag Data can also return
using
the syntax in
.
Field
Value
Description
Read MemBank
1 byte
The MemBank field specifies which of the tag’s memory banks
the data is to be read from. The values correspond to the
Memory Bank values as specified in the
Gen2
specification.
They are:
0x00 = Reserved
0x01 = EPC
0x02= TID
0x03 = User Memory
Read Address
4 bytes
The Address field is the offset in the specified Memory Bank,
in 16-bit words, to start reading from. It corresponds to the
WordPtr
argument in the Gen2 specification.
Note:
Addresses are always zero-based. Specifying 0x00
indicates starting at the first address location.
WordCount
1 byte
The number of words (16 bit chunks) of data to read from
memory bank [MemBank] starting at offset [ReadAddress].
Access Pass-
word
4 byes
The Access Password for the tag, if the tag is read locked. For
an unlocked tag AccessPwd=0x00000000.