64
Sec
tion 4
Writ
e Prot
ect
Func
tion
RFID System
Operation Manual
Section 4
Function
Data Carriers without Batteries
(V600-D23P
@@
)
■
Setting Write Protection Function
The write protect function is set by writing the final address to be protected in address 0000H of the Data
Carrier's memory. The area between address 0001H and the write-protect end address will be write-
protected.
The status of the most significant bit of address 0000H determines whether or not the write protect
function is in effect.
• Write-protect Bit (most significant bit of address 0000H)
1: Write-protected (Yes)
0: Not write-protected (No)
• End Address Setting Range
00H, 01H to 7FH
Addresses 0080H to 00FFH cannot be set as the end address. If the end address is set to 00H, however,
all addresses from 0001H to 00FFH will be protected.
When using the write protect function, write the data in two operations, i.e., one for the write-protected area (address
0000H) of the ID Tag, and one for outside the write-protected area (address 0001H or higher). When the most signifi-
cant bit of address 0000H is 1 and data is written that exceeds the write-protected area (address 0000H) of the ID Tag,
a write protect error will occur.
■
Write-protect Setting Examples (254-byte Memory Data Carrier)
(1)The following settings would write-protect addresses
0001H through 0012H:
(2)The entire memory except address 0000H is write protected by
setting the end address to 00H, as shown below.
(Example: When the end address is 00H)
■
Canceling Write Protection
To cancel write protection, set the most significant bit of address 0000H to 0. The write protection will be
cancelled, and the address set in 0000H will be ignored.
Address 0000H is the write protection setting area.
Therefore, always structure the data so that any data that needs to be write protected is written in addresses starting
from 0001H.
Address
Bit
7
6
5
4
3
2
1
0
0000
Yes/No
End address
0001
00FD
0012
Write-protected
area
Address
0000
0001
00FD
Write-protected
area
Address
0000
Address
Bit
7
6
5
4
3
2
1
0
0000
H
1
0
0
1
0
0
1
0
9
2
Address
Bit
7
6
5
4
3
2
1
0
0000
H
1
0
0
0
0
0
0
0
8
0
Summary of Contents for V600 Series
Page 50: ...48 Section 2 Wiring RFID System Operation Manual Section 2 Installation and Wiring MEMO ...
Page 72: ...70 Section 4 Write Command Memory RFID System Operation Manual Section 4 Function ...
Page 138: ...136 Section 5 End Codes RFID System Operation Manual Section 5 Communications MEMO ...