M24LR64-R_1004 Datasheet, PDF (96/126 Pages) STMicroelectronics – 64 Kbit EEPROM with password protection & dual interface: 400kHz I²C serial bus & ISO 18000-3 mode 1 RF protocol at 13.56MHz

Commands codes
M24LR64-R
26.14
Write-sector Password
On receiving the Write-sector Password command, the M24LR64-R uses the data
contained in the request to write the password and reports whether the operation was
successful in the response. The Option_flag is supported.
During the RF write cycle time, W_t, there must be no modulation at all (neither 100% nor
10%). Otherwise, the M24LR64-R may not correctly program the data into the memory. The
W_t time is equal to t_1nom + 18 × 302 µs. After a successful write, the new value of the
selected password is automatically activated. It is not required to present the new password
value until M24LR64-R power-down.
Table 73. Write-sector Password request format
Request
SOF
Request
_flags
Write-
sector
Password
IC Mfg
code
UID⁽¹⁾
Password
number
8 bits B1h 02h
64 bits
8 bits
1. Gray means that the field is optional.
Data
32 bits
CRC16
Request
EOF
16 bits
Request parameter:
● UID (optional)
● Password number (01h = Pswd1, 02h = Pswd2, 03h = Pswd3, other = Error)
● Data
Table 74. Write-sector Password response format when Error_flag is NOT set
Response
SOF
Response_flags
CRC16
Response
EOF
8 bits
16 bits
Response parameter:
● 32-bit password value. The response is sent back after the write cycle.
Table 75. Write-sector Password response format when Error_flag is set
Response Response_
SOF
flags
Error code
CRC16
Response
EOF
8 bits
8 bits
16 bits
Response parameter:
● Error code as Error_flag is set:
– 02h: the command is not recognized, for example: a format error occurred
– 03h: the option is not supported
– 0Fh: error with no information given
– 10h: the specified block is not available
– 12h: the specified block is locked and its contents cannot be changed.
– 13h: the specified block was not successfully programmed
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Doc ID 15170 Rev 9