Atmel Xplained Evaluation Board AT32UC3A3-XPLD AT32UC3A3-XPLD データシート
製品コード
AT32UC3A3-XPLD
927
32072H–AVR32–10/2012
AT32UC3A3
35.2.2.1
Security measure and control location
A security measure is a mechanism to either block or allow SAB access to a certain address or
address range. A security measure is enabled or disabled by one or several control signals. This
is called the control location for the security measure.
address range. A security measure is enabled or disabled by one or several control signals. This
is called the control location for the security measure.
These security measures can be used to prevent an end user from reading out the code pro-
grammed in the flash, for instance.
grammed in the flash, for instance.
Below follows a more in depth description of what locations are accessible when the security
measures are active.
measures are active.
Table 35-2.
SAB Security measures.
Security measure
Control Location
Description
Security bit
FLASHC security
bit set
Programming and debugging not possible, very restricted
access.
access.
User code
programming
FLASHC UPROT
+ security bit set
Restricts all access except parts of the flash and the flash
controller for programming user code. Debugging is not
possible unless an OS running from the secure part of the
flash supports it.
controller for programming user code. Debugging is not
possible unless an OS running from the secure part of the
flash supports it.
Table 35-3.
Security bit SAB restrictions
Name
Address start
Address end
Access
OCD DCCPU,
OCD DCEMU,
OCD DCSR
0x100000110
0x100000118 Read/Write
User page
0x580800000
0x581000000
Read
Other accesses
-
-
Blocked
Table 35-4.
User code programming SAB restrictions
Name
Address start
Address end
Access
OCD DCCPU,
OCD DCEMU,
OCD DCSR
0x100000110
0x100000118 Read/Write
User page
0x580800000
0x581000000
Read
FLASHC PB
interface
0x5FFFE0000
0x5FFFE0400
Read/Write
FLASH pages
outside
BOOTPROT
0x580000000 +
BOOTPROT size
0x580000000 + Flash size
Read/Write
Other accesses
-
-
Blocked