Omron V720S Series, Руководство по эксплуатации

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Communications Method Section 5-8
5-55
■ Selective Access Operation: In I.CODE1 Mode
■ Exception
（
In I.CODE1 Mode
）
1) When the Tags with the temporary numbers selected by the Tag Selection Command are not pre-
sent, the Reader/Writer returns a communications error to the host.
2) When the Tag Selection Command selects temporary numbers other than those stored by the
Reader/Writer by the Tag Detection Command, the Reader/Writer returns a format error to the
host.
3 The temporary number once stored by the Reader/Writer is not deleted until the Reader/Writer
executes the Stop Command. Commands other than selective access commands (excluding the
Reset Command (XZ)) are not accepted until the Reader/Writer executes the Stop Command.
When the Tag Detection Command has been executed once, it cannot be performed again until
processing has been completed.
How to use properly The Tag Detection Command means that "LT" is set to the "communi-
cations method" for a command frame. Also, the selection of Tag(1)
means that "01" is set to the "communications method " for the com-
mand frame
.
Tag Detection Command (RD)
(Host) (Reader/Writer) (Tag)
Communications process
Tag (0)
Holds a response
Receives a response
Receives a response
Receives a response
Communications process Tag (1)
Detection End Response “72”
Specifies a Tag
Communications process Tag (2)
Response from Tag (2)
Stop command
Removes the stored temporary
numbers
Holds a response
A response which is held Re-
turns (with Temporary No.)
Receives a response
(1) Reader/Writer receives a command
(2) The Reader/Writer communicates with the
Tag; it Adds a temporary number to the re-
sponse and stores it within the Controller.
(3) On completion of communications with all of
the Tags existing in the R/W communications
area. It
Returns in sequence the responses contain-
ing temporary numbers
(4) On completion of responding to all of the Tags, it
returns the Detection End Response (72).
(5) The Reader/Writer receives a Tag Selection
Command containing the temporary number
corresponding to the Tag with which communi-
cations are desired.
(6) The Reader/Writer communications with the
Tag with the specified temporary number.
(7) On receiving the Stop Command, the Controller
removes the stored temporary numbers.