M24LR64-R_1006 Datasheet, PDF (105/128 Pages) STMicroelectronics – 64 Kbit EEPROM with password protection & dual interface

M24LR64-R
Commands codes
26.18
Fast Inventory Initiated
Before receiving the Fast Inventory Initiated command, the M24LR64-R must have received
an Initiate or a Fast Initiate command in order to set the Initiate_ flag. If not, the M24LR64-R
does not answer to the Fast Inventory Initiated command.
On receiving the Fast Inventory Initiated request, the M24LR64-R runs the anticollision
sequence. The Inventory_flag must be set to 1. The meaning of flags 5 to 8 is shown in
Table 26: Request flags 5 to 8 when Bit 3 = 1. The data rate of the response is multiplied by
2.
The request contains:
● the flags,
● the Inventory command code
● the AFI if the AFI flag is set
● the mask length
● the mask value
● the CRC
The M24LR64-R does not generate any answer in case of error.
Table 87. Fast Inventory Initiated request format
Request
SOF
Request
_flags
Fast
Inventory
Initiated
IC Mfg
code
Optional Mask
AFI length
Mask value
8 bits C1h 02h 8 bits 8 bits
0 - 64 bits
CRC16
Request
EOF
16 bits
The Response contains:
● the flags
● the Unique ID
Table 88. Fast Inventory Initiated response format
Response
SOF
Response
_flags
DSFID
UID
8 bits 8 bits
64 bits
CRC16
16 bits
Response
EOF
During an Inventory process, if the VCD does not receive an RF M24LR64-R response, it
waits a time t₃ before sending an EOF to switch to the next slot. t₃ starts from the rising edge
of the request EOF sent by the VCD.
● If the VCD sends a 100% modulated EOF, the minimum value of t₃ is:
t₃min = 4384/f_C (323.3µs) + t_SOF
● If the VCD sends a 10% modulated EOF, the minimum value of t₃ is:
t₃min = 4384/f_C (323.3µs) + t_NRT
where:
● t_SOF is the time required by the M24LR64-R to transmit an SOF to the VCD
● t_NRT is the nominal response time of the M24LR64-R
Doc ID 15170 Rev 10
105/128