XRAG2 memory mapping

XRAG2

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XRAG2 memory mapping

The XRAG2 is a 432-bit memory organized in three memory banks (without the user

memory) or four memory bank (with the user memory) depending on the size of the EPC

code chosen by the user. Each bank is organized as 16-bit words. The reader can read part

or all of each memory bank by 16-bit words. Using the Write command, the device is written

a 16-bit word at a time. The BlockWrite command allows readers to write up to 4 words at a

time. The BlockErase command allows readers to erase several words at a time (from two

words to the entire memory bank).

The bank number and memory organization depend on the size of the EPC contents

programmed in the EPC_length field stored in the first five bits of the Protocol Control (PC)

word.

The sixteen Protocol Control bits are located at memory bit addresses 10h-1Fh of the EPC

bank, as defined in the EPCglobal Class 1 generation 2 RFID UHF specification, revision

1.0.9.

The XRAG2 memory organization is automatically adjusted under the following conditions:

●

a:

–

64-bit Reserved bank,

–

176-bit EPC bank for 128-bit EPC code storage,

–

64-bit TID bank,

–

128-bit User bank,

The memory map corresponding to this configuration is shown in Figure 4.

●

–

64-bit Reserved bank,

–

304-bit EPC bank for 256-bit EPC code storage,

–

64-bit TID bank.

The memory map corresponding to this configuration is shown in Figure 5.