Omron V600 User Manual page 103

Write Protect Function
The write protect function prevents important data stored in the Data Carrier, such as the product type
and model, from being overwritten by other data and lost. Use the following methods to set write
protection after writing important data.
•EEPROM Data Carriers (without Battery)
Setting the Write Protect 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.
Address Bit
0000
•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
Address 0080H to 00FFH can therefore not be set as the end address. If the end address is set to 00H,
however, all addresses from 0001H to 00FFH will be protected.
Write-protect Setting Examples (254-byte Memory Data Carrier)
(1)The following settings would write-protect address-
es 0001H through 0012H:
Address Bit
0000
(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)
Address Bit
0000
Canceling Write Protection
To cancel write protection, turn OFF the most significant bit of address 0000H. 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.
7 6 5 4 3
Yes/
No
7 6 5 4 3
1 0 0 1 0
9
7 6 5 4 3
1 0 0 0 0
8
2 1 0
Address
0000
0001
2 1 0
0 1 0
2
0012
00FD
Address
0000
0001
2 1 0
0 0 0
0
00FD
Section 4
Functions
Write-
protected
area
Write-
protected
area
RFID System
101
User's Manual