Example – ThingMagic M5e-Compact User Manual
Page 81
Application Tag Commands
Command Set
81
Example:
The following EPC IDs (first 3 bits) are in the field:
0xAAAA (101)
0xCCCC (110)
0x4444 (010)
0x3000 (001)
Select Option
= 0x04 (EPC Mem Bank)
Select Data Length
= 0x01 (1 bit)
Select Data
= 0x80
Select Data Address
= 0x00000022 (third bit in the EPC ID)
In this case the third bit of the EPC ID is matched against the first bit of the
Select
Data
value, 1. This would result in the following IDs being returned:
0xAAAA
0x3000
The Select Options field is typically followed by command specific fields. After the command specific fields the fol-
lowing Tag Singulation fields should be specified as appropriate for the Select Contents specified.
Select Address
4 bytes
Contains the offset, in bits, within the memory bank, speci-
fied by the
Option
value, at which the comparison is to start.
NOTE: specifying
Option=0x04
and
Select Address=0x20
is
the equivalent, for Gen2 v1 tags, of specifying
Option=0x01
,
both specify a comparison against the tag EPC ID data.
Note:
Addresses are always zero-based. Specifying 0x00
indicates starting at the first address location.
Select Data Length
1 byte
(
2 bytes if Extended
Data enabled
)
Contains the length of the data (
Select Data
) to be com-
pared, in bits, to the EPC when
Option
=0x01, or to the data
beginning at
Select Address
for other options.
Select Data
M bytes
Contains the data to be compared against the specified tag
data (memory bank and address, or EPC as specified by the
Option
value)
The bit values used start at address 0. So if
Select Data
Length = 2
, i.e. matching 2 bits, then the bits used for com-
parision will be the 2 most significant bits of the
Select Data
value. Examples:
Select Data = 0x00 the bits to match will be 0, 0
Select Data = 0x8F the bits to match will be 1, 0
This is independent of the
Select Data Address
field.
Note:
1- The Select Options field contains multiple sub fields which must be combined into a single Select Options
value. This means the final Select Options value is a result of Select Invert + Select Contents.
Field
Values
Description