37
8331B–AVR–03/12
Atmel AVR XMEGA AU
bits is possible by executing a chip erase command. All other access; using the TIF and OCD, is
blocked if any of the Lock Bits are written to 0. These bits do not block any software access to
the memory.
Note:
1. Program the Fuse Bits and Boot Lock Bits before programming the Lock Bits.
4.17
Register Description – Production Signature Row
4.17.1
RCOSC2M – Internal 2MHz Oscillator Calibration register
• Bit 7:0 – RCOSC2M[7:0]: Internal 2MHz Oscillator Calibration Value
This byte contains the oscillator calibration value for the internal 2MHz oscillator. Calibration of
the oscillator is performed during production test of the device. During reset this value is auto-
matically loaded into calibration register B for the 2MHz DFLL. Refer to
Calibration register B” on page 102
for more details.
4.17.2
RCOSC2MA – Internal 2MHz Oscillator Calibration register
• Bit 7:0 – RCOSC2MA[7:0]: Internal 2MHz Oscillator Calibration Value
This byte contains the oscillator calibration value for the internal 2MHz oscillator. Calibration of
the oscillator is performed during production test of the device. During reset this value is auto-
matically loaded into calibration register A for the 2MHz DFLL. Refer to
Calibration Register A” on page 101
for more details.
Table 4-12.
Lock bit protection mode.
LB[1:0]
Group Configuration
Description
11
NOLOCK3
No lock – no memory locks enabled.
10
WLOCK
Write lock – programming of the flash and EEPROM is
disabled for the programming interface. Fuse bits are
locked for write from the programming interface.
00
RWLOCK
Read and write lock – programming and
read/verification of the flash and EEPROM are disabled
for the programming interface. The lock bits and fuses
are locked for read and write from the programming
interface.
Bit
7
6
5
4
3
2
1
0
+0x00
RCOSC2M[7:0]
RCOSC2M
Read/Write
R
R
R
R
R
R
R
R
Initial Value
x
x
x
x
x
x
x
x
Bit
7
6
5
4
3
2
1
0
+0x01
RCOSC2MA[7:0]
RCOSC2MA
Read/Write
R
R
R
R
R
R
R
R
Initial Value
x
x
x
x
x
x
x
x
