DocID15687 Rev 5

19/29

PM0059

Flash memory interface

28

Write protection error flag

If an erase/program operation to a write protected area of the Flash memory is performed,

the Write Protection Error flag (WRPERR) is set in the FLASH_SR register.

If an erase operation is requested, the WRPERR bit is set when:

•

Mass or sector erase are configured (MER or MER/MER1 and SER = 1)

•

A sector erase is requested and the Sector Number SNB field is not valid

•

A mass erase is requested while at least one of the user sector is write protected by

option bit (MER or MER/MER1 = 1 and nWRPi = 0 with 0 ≤ i ≤ 11 bits in the

FLASH_OPTCRx register

•

The Flash memory is readout protected and an intrusion is detected.

If a program operation is requested, the WRPERR bit is set when:

•

A write operation is performed on system memory or on the reserved part of the user

specific sector.

•

A write operation is performed to the user configuration sector

•

A write operation is performed on a sector write protected by option bit.

•

A write operation is requested on an OTP area which is already locked

•

The Flash memory is read protected and an intrusion is detected.

2.7

One-time programmable bytes

Table 9

shows the organization of the one-time programmable (OTP) part of the OTP area.

The OTP area is divided into 16 OTP data blocks of 32 bytes and one lock OTP block of 16

bytes. The OTP data and lock blocks cannot be erased. The lock block contains 16 bytes

LOCKBi (0

≤ i ≤ 15) to lock the corresponding OTP data block (blocks 0 to 15). Each OTP

data block can be programmed until the value 0x00 is programmed in the corresponding

OTP lock byte. The lock bytes must only contain 0x00 and 0xFF values, otherwise the OTP

bytes might not be taken into account correctly.

Table 9. OTP part organization

Block

[128:96]

[95:64]

[63:32]

[31:0]

Address byte 0

0

OTP0

OTP0

OTP0

OTP0

0x1FFF 7800

OTP0

OTP0

OTP0

OTP0

0x1FFF 7810

1

OTP1

OTP1

OTP1

OTP1

0x1FFF 7820

OTP1

OTP1

OTP1

OTP1

0x1FFF 7830

.

.

.

.

.

.

.

.

.

15

OTP15

OTP15

OTP15

OTP15

0x1FFF 79E0

OTP15

OTP15

OTP15

OTP15

0x1FFF 79F0

Lock block

LOCKB15 ...

LOCKB12

LOCKB11 ...

LOCKB8

LOCKB7 ...

LOCKB4

LOCKB3 ...

LOCKB0

0x1FFF 7A00