5-2 Control Procedures for Each Communication
5-2
5-14
5-2-4 Selective Access
Selective Access is a function to communicate with the specified Tags among multiple Tags in
the antenna communication area. The processes vary depending on the Reader/Writer’s mode.
5-2-4-1 ISO Mode
First, the Reader/Writer reads out the UID of the Tag in the communication area using Read
Command (in multiple processing modes). The UID is readable when UID/SNR addition
setting option is enabled in advance using the respective command (SN). When the UID is
already identified, the execution of Read Command can be skipped. Then, the Reader/Writer
communicates with the specified Tag based on the obtained UID.
(1) The Reader/Writer reads the UID of the Tag using Read Command.
It reads out UID data of the Tag by executing a Multiple Trigger Mode command with its
UID/SNR addition setting enabled.
1
2
3
(2) The Reader/Writer communicates with the specified Tag (No. 2 in the figure below) by
specifying the UID obtained in 1 using UID Select Read/Write command.
The ReaderWriter communicates with the Tag specified by the UID. For UID Select
Command, specify SL for the communication, and specify the UID of the communication
target Tag in the UID area in hex number, 123.
1
2
3
Note:
Some Tags detected by UID read (Tag detection) may not be communicated with Selective Access mode using UID
Select (Tag designation) command, depending on the Tag conditions (the distances between the antenna and tag,
or those between the Tag and another Tag). This is especially true when the Tag exists in the boundary area of
the communication area. The operating system must be configured to check the number of detected Tags against
the number of Tags the Reader/Writer communicated with (or the number of the actual Tags).
