Alien Technology ALR-8780, Interface Manual

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C
HAPTER
4 A
LIEN
R
EADER
P
ROTOCOL
R
EADER
I
NTERFACE
G
UIDE
D
OC
. C
ONTROL
# 8101938-000 R
EV
05
57
I
NVENTORY
The Inventory acquire mode performs a full anti-collision search on tags in the
reader’s field of view. This method will locate and distinguish multiple tags in front
of the reader at the same time.
G
LOBAL
S
CROLL
The Global Scroll acquire mode instructs the reader to read a single tag
repeatedly. This is a very fast tag reading method that is most effective when
only one tag at a time is expected to be within reader range, as in conveyor belt
applications. Under such circumstances, the performance for single tag reading
is considerably faster than repeatedly doing a full tag search using the Inventory
mode.
NOTE: If multiple tags are in range of the reader when this mode is used, the
reader will either select one of the tags (usually the “strongest’” or “loudest”) to
read and report, or will read none of the tags.
NOTE: Changes made with this command will take effect immediately.
AcquireMode Examples
Command
Response >set AcquireMode = Global Scroll
AcquireMode = Global Scroll
Command
Response >set AcquireMode = Inventory
AcquireMode = Inventory
TagType
9800 | 9780 | 8780 | 9640 | 9774
There are currently five types of tags supported by Alien RFID readers, each
implementing one of the three EPCglobal air protocols.
By allowing the reader to ignore certain tag types, the reader can focus its
attention and spend more time acquire tags at a higher speed. This is
accomplished by setting the TagType property. The TagType value is a bitmap,
where each bit enables a certain tag type, as summarized in the following table.
TagType
Bit
Tag
Enabled
Air
Protocol
9800 9780 8780 9640 9770
Bit 1 "Quark"
✔ ✔ * ✔ ✔
Bit 2 "Omega"
✔ ✔ * ✔ ✔
Bit 3 "Lepton"
Class 1 / Gen 1
✔ ✔ ✔ ✔ ✔
Bit 4 C0 Class 0
✔
- - -
✔
Bit 5 C1G2 Class 1 / Gen 2
✔
- - - -
Bit 6 reserved
Bit 7 reserved
Bit 8 reserved