
RM0453 Rev 2
149/1454
RM0453
Embedded Flash memory (FLASH)
153
4.10.20 FLASH secure SRAM start address and CPU2 reset vector register
(FLASH_SRRVR)
Address offset: 0x084
Reset value: 0xFFFF 8000
Default reset value from ST production is given. Subsequently, 0bXXXX XXX1 XXXX XX11
XXXX XXXX XXXX XXXX The option bits are loaded with user values from the Flash
memory at power-on reset release.
When the system is secure (ESE = 1), this register provides write access security and can
only be written by the CPU2. A write access from the CPU1 is ignored and an illegal access
event is generated. On any read access, the register value is returned.
When the system is secure (ESE = 1), this register is further more protected by the
PRIVMODE. When privilege protection is enabled in PRIVMODE, this register provides
Bit 23
HDPAD:
user Flash memory hide protection area disable
When FSD = 1, the user Flash memory hide protection area is disabled whatever the value
of this HDPAD bit.
This bit is write protected when HDPAD = 0 and HDPADIS = 1.
0 (and FSD = 0): User Flash memory hide protection area enabled. HDPSA[6:0] contains
the start address of the first 2-Kbyte page of the user Flash memory hide protection area.
1 (and FSD = 0): User Flash memory hide protection area disabled
Bits 22:16
HDPSA[6:0]:
user Flash memory hide protection area start address
This bit is write protected when HDPAD = 0 and HDPADIS = 1.
When FSD = HDPAD = 0, the user Flash memory hide protection area enabled.
HDPSA[6:0] contain the start address of the first 2-Kbyte page of the user Flash memory
hide protection area.
0x00: Flash memory hide protection start address offset 0x0000 0000
0x01: Flash memory hide protection start address offset 0x0000 0800
...
0x7F: Flash memory hide protection start address offset 0x0003 F800
Bits 15:13 Reserved, must be kept at reset value.
Bit 12
DDS:
CPU2 debug access disable
0: CPU2 debug access enabled. (when also enabled by C2SWDBGEN)
1: CPU2 debug access disabled.
Bits 11:8 Reserved, must be kept at reset value.
Bit 7
FSD:
Flash memory security disabled.
This bit is write protected when HDPAD = 0 and HDPADIS = 1.
0: System and Flash memory secure (Flash memory secure area given be SFSA[6:0])
1: System and Flash memory non-secure
Bits 6:0
SFSA[6:0]:
secure Flash memory start address
This bit is write protected when HDPAD = 0 and HDPADIS = 1.
When FSD = 0, the system and Flash memory are secure. SFSA[6:0] contains the page
number of the first 2-Kbyte page of the secure Flash memory area.
0x00: secure Flash memory start address offset 0x0000 0000
0x01: secure Flash memory start address offset 0x0000 0800
...
0x7F: secure Flash memory start address offset 0x0003 F800