Omron V680S Series, Руководство пользователя

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Sec
tion 6
RF Ta
g Co
mm
u
n
icat
ions
Section 6
Functions
107
RFID System
User's Manual
(Modbus TCP)
Normal RF Tag Communications
Communications with the RF Tag are performed by using the queries that are listed in the following
table.
Tag Memory Management

RF TAG OVERWRITE COUNT CONTROL Query
This query can be used to determine whether the RF Tag overwrite limit has been exceeded.
•
With the RF TAG OVERWRITE COUNT CONTROL query with a subtraction specification, the
overwrite count is subtracted from the data in the user-specified overwrite count control area to
determine whether the number of overwrites has been exceeded.
•
With the RF TAG OVERWRITE COUNT CONTROL query with an addition specification, the
overwrite count is added to the data in the user-specified overwrite count control area to determine
whether the number of overwrites has exceeded 100,000.
•
The RF TAG OVERWRITE COUNT CONTROL query with an addition specification is designed for
use with an RF Tag write life of 100,000. The overwrite count control area must be set so that it is all
within one block.
RF TAG OVERWRITE COUNT CONTROL Query with a Subtraction Specification
The overwrite count control area consists of 4 bytes from the specified start address. The decrement
value is subtracted from the overwrite count and then written to this area. When the value reaches 0
(i.e., 00 hex), a warning code is returned. Therefore, to enable control of the number of overwrites,
the maximum number of overwrites must be written to the overwrite count control area beforehand.
You can set any number of overwrites up to 16,700,000.
You can read the overwrite count control area with a read query. If the control area data is already 0,
the control area value will not be refreshed, and a warning code will be returned as a response.
When the refresh count is set to 0000 hex, the count will not be updated, and only an overwrite count
check will be performed.
Name Description Page
READ DATA Reads data from an RF Tag. p.170
WRITE DATA Writes data to the memory of the RF Tag. p.171
READ ID Reads the RF Tag’s ID code. p.172
DATA FILL Writes the specified data to the specified number of words beginning from the specified start
address. The specifications are made in the query.
p.175
LOCK Locks the specified memory block in the RF Tag. It will no longer be possible to write data to the
locked memory block. The lock cannot be released.
p.176
DATA COPY Reads data from the memory of an RF Tag using one Reader/Writer (A) and writes it to the
memory of the RF Tag in the communications field of another Reader/Writer (B).
p.173
2 w ords (4 b ytes)
O v er w rite co u nt control area Al w ays 00 hex
Lo w er digit
Middle digit
Upper digit