Atmel Xplained Evaluation Board AT32UC3A3-XPLD AT32UC3A3-XPLD データシート
製品コード
AT32UC3A3-XPLD
136
32072H–AVR32–10/2012
AT32UC3A3
set and the command is cancelled. If the bit LOCKE has been written to 1 in FCR, the interrupt
line rises.
line rises.
When the command is complete, the bit FRDY bit in the Flash Status Register (FSR) is set. If an
interrupt has been enabled by setting the bit FRDY in FCR, the interrupt line of the flash control-
ler is set. Two errors can be detected in the FSR register after issuing the command:
interrupt has been enabled by setting the bit FRDY in FCR, the interrupt line of the flash control-
ler is set. Two errors can be detected in the FSR register after issuing the command:
• Programming Error: A bad keyword and/or an invalid command have been written in the
FCMD register.
• Lock Error: At least one lock region to be erased is protected, or BOOTPROT is different from
0. The erase command has been refused and no page has been erased. A Clear Lock Bit
command must be executed previously to unlock the corresponding lock regions.
command must be executed previously to unlock the corresponding lock regions.
12.5.3
Region lock bits
The flash block has p pages, and these pages are grouped into 16 lock regions, each region
containing p/16 pages. Each region has a dedicated lock bit preventing writing and erasing
pages in the region. After production, the device may have some regions locked. These locked
regions are reserved for a boot or default application. Locked regions can be unlocked to be
erased and then programmed with another application or other data.
containing p/16 pages. Each region has a dedicated lock bit preventing writing and erasing
pages in the region. After production, the device may have some regions locked. These locked
regions are reserved for a boot or default application. Locked regions can be unlocked to be
erased and then programmed with another application or other data.
To lock or unlock a region, the commands Lock Region Containing Page (LP) and Unlock
Region Containing Page (UP) are provided. Writing one of these commands, together with the
number of the page whose region should be locked/unlocked, performs the desired operation.
Region Containing Page (UP) are provided. Writing one of these commands, together with the
number of the page whose region should be locked/unlocked, performs the desired operation.
One error can be detected in the FSR register after issuing the command:
• Programming Error: A bad keyword and/or an invalid command have been written in the
FCMD register.
The lock bits are implemented using the lowest 16 general-purpose fuse bits. This means that
lock bits can also be set/cleared using the commands for writing/erasing general-purpose fuse
bits, see chapter 12.6. The general-purpose bit being in an erased (1) state means that the
region is unlocked.
lock bits can also be set/cleared using the commands for writing/erasing general-purpose fuse
bits, see chapter 12.6. The general-purpose bit being in an erased (1) state means that the
region is unlocked.
The lowermost pages in the Flash can additionally be protected by the BOOTPROT fuses, see
12.6
General-purpose fuse bits
Each flash block has a number of general-purpose fuse bits that the application programmer can
use freely. The fuse bits can be written and erased using dedicated commands, and read
use freely. The fuse bits can be written and erased using dedicated commands, and read