XRAG2_08 Datasheet, PDF (26/33 Pages) STMicroelectronics – 432-bit UHF, EPCglobal Class1 Generation2 and ISO 18000-6C, contactless memory chip with user memory

XRAG2 command descriptions
XRAG2
8.3
8.3.1
8.3.2
8.3.3
8.3.4
Access command set
The set of access commands comprises Req_RN, Access, Read, Write, BlockWrite,
BlockErase, Kill and Lock.
As described in the EPCglobal Class 1 generation 2 RFID UHF specification, revision 1.0.9,
the XRAG2 executes Req_RN from the Acknowledged, Open, or Secured states.
The XRAG2 executes Read, Write, BlockWrite and BlockErase instructions from the
Secured state. If allowed by the lock status of the addressed location, the Read, Write,
BlockWrite and BlockErase instructions can be executed from the Open state.
The XRAG2 executes the Kill and Access commands from the Open or Secured states.
The XRAG2 executes the Lock command only from the Secured state.
Req_RN
The XRAG2 supports the Req_RN command as described in the EPCglobal Class 1
generation 2 RFID UHF specification, revision 1.0.9.
The Req_RN command instructs the tag in Acknowledged, Open or Secured state to
backscatter a new RN16. If the tag is in the Acknowledged state, the new RN16 becomes
the handle of the tag for all subsequent access commands. The handle is a tag identification
number used for subsequent access commands. If the tag is in the Open or Secured state,
a new RN16 is backscattered without changing the tag handle.
Access
The XRAG2 supports the Access command as described in the EPCglobal Class 1
generation 2 RFID UHF specification, revision 1.0.9.
The Access command allows the reader to put tags with non-zero access passwords in the
Secured state.
Read
The XRAG2 supports the Read command as described in the EPCglobal Class 1
generation 2 RFID UHF specification, revision 1.0.9.
The Read command allows the reader to read a part or all of the tag Reserved, EPC, TID or
User memory banks.
Write
The XRAG2 supports the Write command as described in the EPCglobal Class 1 generation
2 RFID UHF specification, revision 1.0.9.
The Write command allows the reader to write a 16-bit word into the Reserved, EPC, or
User memory bank. The 16-bit data word is cover-coded by the reader during the Write
command using a new RN16 number generated using a Req_RN instruction before each
Write command. The Write cycle executes an auto-erase cycle before word programming.
After completion of the Write operation, the XRAG2 backscatters a single bit header (0b), its
handle and a CRC16 within t_WRITE. The XRAG2 backscatters the non-specific error code
0Fh within t_WRITE if an error is encountered during the transmission of the Write command.
The duration of the Write cycle t_WRITE is specified in Table 11.
26/33