AN3171

M24LR64-R memory organization

Doc ID 17229 Rev 1

11/14

3.2.2

I²C_Write_Lock bits

Eight bytes in the system memory area define the I²C_Write_Lock bit value of each sector in

user memory (1 bit for 1 sector).

The I²C_Write_Lock bits can be read through the I²C bus to verify the protection of the user

memory in RF mode.

The C_Write_Lock bits can be modified through the I²C bus only if the I²C password has

been successfully presented.

3.2.3

System parameters

The system parameters (in the system memory) are:

●

I²C password

●

three RF passwords

●

DSFID

●

AFI

●

two RFU bytes

●

eight UID bytes

●

three Mem_Size bytes

●

IC Ref

These parameters are read-only. Table 5 shows there location in the system memory.

E2 = 1

44

SSS 47

SSS 46

SSS 45

SSS 44

E2 = 1

48

SSS 51

SSS 50

SSS 49

SSS 48

E2 = 1

52

SSS 55

SSS 54

SSS 53

SSS 52

E2 = 1

56

SSS 59

SSS 58

SSS 51

SSS 56

E2 = 1

60

SSS 63

SSS 62

SSS 61

SSS 60

Table 3.

RF block security status (continued)

Bits [31:24]

Bits [23:16]

Bits [15:8]

Bits [7:0]

Table 4.

I2C_Write_Lock bits

Bits [31:24]

Bits [23:16]

Bits [15:8]

Bits [7:0]

E2 = 1

2048

sectors 31-24

sectors 23-16

sectors 15-8

sectors 7-0

E2 = 1

2052

sectors 63-56

sectors 55-48

sectors 47-40

sectors 39-32