Omron V680-CA1D, Руководство пользователя

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Heat-resistive RFID System
User's Manual
Section 4
Reading from/Writing to Tags
• MDS Command
The overwrite count control area consists of 3 bytes
from the start address. The decrement value from
the overwrite count is written in this area, and if this
value is 0 (00H), an end code 76 will be given as a
warning. Therefore, to enable control of the number
of overwrites, the maximum number of overwrites
must be written to the overwrite count control area
beforehand.
The user-specified number of overwrites can be set
to up to 16,700,000. The number of overwrites in the
specifications for Tags, however, is 100,000
overwrites (0186A0H), so be sure to set the number
of overwrites to 100,000 or lower. The number of
overwrites is controlled using hexadecimal values,
and can be read using the READ command.
If the control area data is already 0, the control area
value will not be refreshed, and only a warning will
be returned as a response. When the refresh count
is set as 00H, the count will not be updated, and only
an overwrite count check will be performed.
Example Using the OVERWRITE COUNT (MDS) Command
Area start address
→
Upper digit
Middle digit
3 bytes
Lower digit
(1) The overwrite count of 100,000 times is written.
@
××
WTH10010186A0[FCS]
*
CR
(2) Enter the overwrite count of 5.
@
××
MDS1001005[FCS]
*
CR
A total of 5 times will be decremented from
100,000.
(3) The accumulated count is 100,000 times.
"MD76" (overwrite count exceeded)
0 4
H
9 3
H
E 0
H
0010
0011
0012
0 4
H
9 3
H
D B
H
0010
0011
0012
0 0
H
0 0
H
0 0
H
0010
0011
0012