Omron V720 Series, Руководство по эксплуатации

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Single, FIFO, Multiple, and Selective Access Functions
Section 3-1
3-2
3-1 Single, FIFO, Multiple, and Selective Access Functions
Four communication modes are available depending on the number or state
of Tags in the communication area. Commands can be used for selecting
one of them. Refer to Section 5 Communications Functions for details.
Single Access Mode
In this mode, only a single Tag can be in the communications area,
otherwise a communications error will result.
FIFO Access Mode
In the FIFO (first-in, first-out) Access Mode, the RFID System reads and
writes data to and from each Tag coming into the communications area one
after another. Since every Tag finished with communications is set to access
prohibit, communications will be possible if only one Tag newly arrives in the
communication area of the Antenna where more than one Tag exists. An
error results, however, if two or more Tags arrive in the communications area
simultaneously. When the access-prohibited Tag moves out of the
communications area, communications will become possible again.