M24256-DRMN6TP Datasheet, PDF (21/40 Pages) STMicroelectronics – 256-Kbit serial I²C bus EEPROM

M24256-BW M24256-BR M24256-BF M24256-DR M24256-DF
Initial delivery state
5.4
Read the lock status (M24256-D only)
The locked/unlocked status of the Identification page can be checked by transmitting a
specific truncated command [Identification Page Write instruction + one data byte] to the
device. The device returns an acknowledge bit if the Identification page is unlocked,
otherwise a NoAck bit if the Identification page is locked.
Right after this, it is recommended to transmit to the device a Start condition followed by a
Stop condition, so that:
● Start: the truncated command is not executed because the Start condition resets the
device internal logic,
● Stop: the device is then set back into Standby mode by the Stop condition.
6
Initial delivery state
The device is delivered with all the memory array bits and Identification page bits set to 1
(each byte contains FFh).
Doc ID 6757 Rev 30
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