M24LR64-R_1006 Datasheet, PDF (68/128 Pages) STMicroelectronics – 64 Kbit EEPROM with password protection & dual interface

Anticollision
M24LR64-R
Figure 50. Principle of comparison between the mask, the slot number and the UID
Mask value received in the Inventory command
The Mask value less the padding 0s is loaded
into the Tag comparator
The Slot counter is calculated
Nb_slots_flags = 0 (16 slots), Slot Counter is 4 bits
MSB
LSB
0000 0100 1100 1111 _b 16 bits
MSB
LSB
100 1100 1111 _b 11 bits
MSB LSB
xxxx
4 bits
The Slot counter is concatened to the Mask value
Nb_slots_flags = 0
MSB
LSB
xxxx 100 1100 1111 _b 15 bits
The concatenated result is compared with
the least significant bits of the Tag UID.
b63
UID
b0
xxxx xxxx ..... xxxx xxxx x xxx xxxx xxxx xxxx _b 64 bits
Bits ignored
Compare
AI06682
The AFI field is present if the AFI_flag is set.
The pulse is generated according to the definition of the EOF in ISO/IEC 15693-2.
The first slot starts immediately after the reception of the request EOF. To switch to the next
slot, the VCD sends an EOF.
The following rules and restrictions apply:
● if no M24LR64-R answer is detected, the VCD may switch to the next slot by sending
an EOF,
● if one or more M24LR64-R answers are detected, the VCD waits until the complete
frame has been received before sending an EOF for switching to the next slot.
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Doc ID 15170 Rev 10