![GigaDevice Semiconductor GD32E23 Series Скачать руководство пользователя страница 52](http://html.mh-extra.com/html/gigadevice-semiconductor/gd32e23-series/gd32e23-series_user-manual_2225794052.webp)
GD32E23x User Manual
52
Address
Name
Description
1: Software free watchdog timer
0x1fff f803
OB_USER_N
OB_USER complement value
0x1fff f804
OB_DATA[7:0]
user defined data bit 7 to 0
0x1fff f805
OB_DATA_N[7:0]
OB_DATA complement value bit 7 to 0
0x1fff f806
OB_DATA[15:8]
user defined data bit 15 to 8
0x1fff f807
OB_DATA_N[15:8]
OB_DATA complement value bit 15 to 8
0x1fff f808
OB_WP[7:0]
Page Erase/Program Protection bit 7 to 0
0x1fff f809
OB_WP_N[7:0]
OB_WP complement value bit 7 to 0
0x1fff f80a
OB_WP[15:8]
Page Erase/Program Protection bit 15 to 8
0x1fff f80b
OB_WP_N[15:8]
OB_WP complement value bit 15 to 8
2.3.11.
Page erase/Program protection
The FMC provides page erase/program protection functions to prevent inadvertent
operations on the flash memory. The page erase or program will not be accepted by the
FMC on protected pages. If the page erase or program command is sent to the FMC on a
protected page, the WPERR bit in the FMC_STAT register will then be set by the FMC. If the
WPERR bit is set and the ERRIE bit is also set to 1 to enable the corresponding interrupt,
then the flash operation error interrupt will be triggered by the FMC to get the attention of the
CPU. The page protection function can be individually enabled by configuring the
OB_WP[15:0] bit field to 0 in the option byte. If a page erase operation is executed on the
Option Byte region, all the flash memory page protection functions will be disabled. When
setting or resetting OB_WP in the option byte, the software need to set OBRLD in FMC_CTL
register or a system reset to reload the OB_WP bits. The
Table 2-4. OB_WP bit for pages
shows which pages are protected by set OB_WP[15:0].
Table 2-4. OB_WP bit for pages protected
OB_WP bit
pages protected
OB_WP[0]
page 0 ~ page 3
OB_WP[1]
page 4 ~ page 7
OB_WP[2]
page 8 ~ page 11
.
.
.
.
.
.
OB_WP[14]
page 56 ~ page 59
OB_WP[15]
page 60 ~ page 63
2.3.12.
Security protection
The FMC provides a security protection function to prevent illegal code/data access on the
flash memory. This function is useful for protecting the software/firmware from illegal users.
There are 3 levels for protecting: