M24LR16E-R block securiity in I2C mode

danfarrelly9 · ‎2015-09-17

Posted on September 17, 2015 at 17:27

Hello

I am using an M24LR16E-R eeprom in I2C mode.

I have written to the I2C_Write_Lock bits and have set sector 0 as write-protected. Process as follows:

Present Password command

Write I2C_Write_Lock bit (0x0001) //to set sector 0 as protected

I have read the write lock bits afterwards and confirmed that they have been changed. However, when I have tried to write to sector 0, it is still possible to write the memory sector despite the lock bit being set.

Have I missed a step? Any help would be much appreciated.

Cheers

Dan

#m24lr16e #stm32l-m24lr16e-i2c

Nickname6430_O · ‎2015-11-13

Posted on November 13, 2015 at 15:18

Hello Dan,

as far as i know You can write to this sector because You have rights to it from Present Password command. This command remains active until the M24LR is powered off or unit a new I2C present password command is issued. Plese try this and let me know.

Regards

Petr

View solution in original post

Nickname6430_O · ‎2015-11-13

Posted on November 13, 2015 at 15:18

Hello Dan,

as far as i know You can write to this sector because You have rights to it from Present Password command. This command remains active until the M24LR is powered off or unit a new I2C present password command is issued. Plese try this and let me know.

Regards

Petr

Nickname5101_O · ‎2015-11-17

Posted on November 17, 2015 at 15:46

Hello ,

basic sequence is

1) present valid I2C password

2) protect zone by writing correspondant I2C write lock bit

this protection will be activated on only after presenting a bad password or after a POR ,

3) each time The valid I2C password is presented , sector writing is possible , I2C password act as a Super User . until next POR or presentation of a bad Password .