WM710xx – Secure F-RAM with Gen-2 RFID
DSPI
Address
…
0x3DA
0x3DB
0x3DC
0x3DD
0x3DE
…
0x3EA
0x3EB
0x3EC
0x3ED
0x3EE
…
0x3F3
0x3F4
0x3F5
0x3F6
0x3F7
0x3F8
0x3F9
0x3FA
0x3FB
0x3FC
0x3FD
0x3FE
0x3FF
Gen-2
Memory Bank
…
USER
USER
USER
USER
USER
…
USER
USER
USER
USER
USER
…
USER
USER
USER
USER
USER
USER
USER
USER
USER
USER
USER
USER
USER
Gen-2
Address
…
0x3C6
0x3C7
0x3C8
0x3C9
0x3CA
…
0x3D6
0x3D7
0x3D8
0x3D9
0x3DA
…
0x3DF
0x3E0
0x3E1
0x3E2
0x3E3
0x3E4
0x3E5
0x3E6
0x3E7
0x3E8
0x3E9
0x3EA
0x3EB
Word
Pointer
(EBV8)
…
0x8746
0x8747
0x8748
0x8749
0x874A
…
0x8756
0x8757
0x8758
0x8759
0x875A
…
0x875F
0x8760
0x8761
0x8762
0x8763
0x8764
0x8765
0x8766
0x8767
0x8768
0x8769
0x876A
0x876B
Description
16k Memory: END
(BLK_SIZE = 2 words/block)
16k Memory: END
(BLK_SIZE = 4 words/block)
16k Memory: END
(BLK_SIZE = 8 words/block)
16k Memory: END
(BLK_SIZE = 16 words/block)
16k Memory: END
(BLK_SIZE = 32 words/block)
(BLK_SIZE > 32 words/block)
RESERVED
RESERVED
RESERVED
RESERVED
GEN2 WM710XX MEMORY BANKS
The RFID memory banks reside in Ramtron‟s non-volatile F-RAM memory. F-RAM brings many benefits to
the WM710xx. The first benefit is the size of the memory itself – up to 16k-bit, most of which is available in
the USER memory bank. F-RAM‟s impact on the Gen2 protocol is most dramatically seen when writing to
WM710xx memory. Unlike EEPROM memory, no charge pump or memory soak time is required to write to
WM710xx memory, resulting in zero time and zero power penalties. The write cycle is completed
immediately, allowing an interrogator to continue writing additional data to memory with no time penalty
incurred due to the memory itself. A comparison between F-RAM and EEPROM memories is shown in Figure
INVENTORY, and ACCESS sequence of commands to write a data word to memory. The same interrogator
command sequence is transmitted to the WM710xx and an EEPROM-based RFID. The effect of the EEPROM
time penalty is shown within the context of the protocol.
Rev. 1.4
May 2011
Page 5 of 24
RAMTRON [ RAMTRON INTERNATIONAL CORPORATION ]
