Option Byte Description; Table 11. Option Byte Format; Table 12. Option Byte Organization - STMicroelectronics RM0365 Reference Manual

RM0365
5

Option byte description

There are eight option bytes. They are configured by the end user depending on the
application requirements. As a configuration example, the watchdog may be selected in
hardware or software mode.
A 32-bit word is split up as follows in the option bytes.
Complemented option
The organization of these bytes inside the information block is as shown in
The option bytes can be read from the memory locations listed in
Option byte register (FLASH_OBR).
Note: The new programmed option bytes (user, read/write protection) are loaded after a system
reset.
Address
0x1FFF F800
0x1FFF F804
0x1FFF F808
0x1FFF F80C
1. Available only on STM32F302xB/C/D/E. Must be kept at reset values in STM32F302x6/8 devices.
31-24
Option byte 1
byte1

Table 12. Option byte organization

[31:24]
nUSER
nData1
nWRP1
(1)
nWRP3
DocID025202 Rev 7

Table 11. Option byte format

23-16
Complemented option
[23:16]
USER
Data1
WRP1
(1)
WRP3
Option byte description
15 -8
Option byte 0
byte0
Table
Table 12 or from the
[15:8]
nRDP
nData0
nWRP0
(1)
nWRP2
7-0
12.
[7:0]
RDP
Data0
WRP0
(1)
WRP2
78/1080
80