AT32UC3L064_1 ATMEL [ATMEL Corporation], AT32UC3L064_1 Datasheet - Page 48

• Manufacturer Part Number: AT32UC3L064_1
• Description: AVR32 32-bit Microcontroller
• Manufacturer: ATMEL [ATMEL Corporation]

7.5.3
7.6
32099A–AVR32–06/09
General-purpose Fuse Bits
Region Lock Bits
flash memory locations, the general-purpose fuse bits, and the security bit are erased (reset to
0xFF) after an Erase All.
The EA command also ensures that all volatile memories, such as register file and RAMs, are
erased before the security bit is erased.
Erase All operation is allowed only if no regions are locked, and the BOOTPROT fuses are
configured with a BOOTPROT region size of 0. Thus, if at least one region is locked, the bit
LOCKE in FSR is set and the command is cancelled. If the LOCKE bit in FCR is one, an inter-
rupt request is set generated.
When the command is complete, the FRDY bit in the Flash Status Register (FSR) is set. If an
interrupt has been enabled by writing FCR.FRDY to one, an interrupt request is generated.
Two errors can be detected in the FSR register after issuing the command:
The flash memory 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.
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.
One error can be detected in the FSR register after issuing the command:
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
region is unlocked.
The lowermost pages in the flash can additionally be protected by the BOOTPROT fuses, see
Section
The flash memory 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
• Programming Error: A bad keyword and/or an invalid command have been written in the
• Lock Error: At least one lock region is protected, or BOOTPROT is different from 0. The
• Programming Error: A bad keyword and/or an invalid command have been written in the
FCMD register.
erase command has been aborted and no page has been erased. A “Unlock region
containing given page” (UP) command must be executed to unlock any locked regions.
FCMD register.
7.6.
Section
7.6. The general-purpose bit being in an erased (1) state means that the
AT32UC3L
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