User's Manual

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Section 3 ID Tags
RFID System
User's Manual
Section 3
Functions and Operation
Write Protection
The write protection function protects important data stored in the memory of a ID Tag, such as the
product model or type, from being overwritten inadvertently.
Enable the write protection function after writing important data as described in this section.
 Setting Write Protection
For the write protection function to be effective, it must be enabled or disabled in both the DeviceNet
Remote ID Controller settings and the ID Tag settings.
1. Enabling the Write Protection for the DeviceNet Remote ID Controller
The write protection function can be enabled or disabled by setting the write-protect bit of the DeviceNet Remote ID Controller in
the I/O Allocation Table.
Refer to the Signal Names and Functions for details.
p.49
2. Setting Write Protection in ID Tags
Write protection for individual ID Tags is set in the most significant bit of address 0000H.
Write protection is set in the 4 bytes from Tag address 0000H to 0003H.
• Write-protect bit (most significant bit of address 0000H)
1: Write-protected (Enable)
0: Not write-protected (Disable)
• Addresses in Tag Memory That Can Be Write Protected
Start address: 0000H to 7FFFH
End address: 0000H to FFFFH
The ID Tag write protection setting area (addresses 0000 hex to 0003 hex) can be used as user memory if the write
protection function is not used. To use the ID Tag’s write protection setting area (addresses 0000 hex to 0003 hex) as
user memory, be sure to disable write protection by setting the Write Protect Bit in the DeviceNet Remote ID Controller.
Address Bit 7 6 5 4 3 2 1 0
0000H Enable/disable Upper two digits of start address (00 to 7F)
0001H Lower two digits of start address (00 to 7F)
0002H Upper two digits of end address (00 to 7F)
0003H Lower two digits of end address (00 to 7F)