![](http://datasheet.mmic.net.cn/30000/MR80C32-20-D_datasheet_2377239/MR80C32-20-D_265.png)
265
8154B–AVR–07/09
ATmega16A
Notes:
1. Program the Fuse bits before programming the Lock bits.
2. “1” means unprogrammed, “0” means programmed
26.2
Fuse Bits
of all the fuses and how they are mapped into the fuse bytes. Note that the fuses are read as
logical zero, “0”, if they are programmed.
Notes:
1. The SPIEN Fuse is not accessible in SPI Serial Programming mode.
2. The CKOPT Fuse functionality depends on the setting of the CKSEL bits. See
See “Clock40
1
LPM executing from the Boot Loader section is not allowed to
read from the Application section. If interrupt vectors are placed
in the Boot Loader section, interrupts are disabled while
executing from the Application section.
BLB1 Mode
BLB12
BLB11
11
1
No restrictions for SPM or LPM accessing the Boot Loader
section.
2
1
0
SPM is not allowed to write to the Boot Loader section.
30
0
SPM is not allowed to write to the Boot Loader section, and LPM
executing from the Application section is not allowed to read
from the Boot Loader section. If interrupt vectors are placed in
the Application section, interrupts are disabled while executing
from the Boot Loader section.
40
1
LPM executing from the Application section is not allowed to
read from the Boot Loader section. If interrupt vectors are
placed in the Application section, interrupts are disabled while
executing from the Boot Loader section.
Table 26-2.
Lock Bit Protection Modes (Continued)
Memory Lock Bits(2)
Protection Type
Table 26-3.
Fuse High Byte
Fuse High
Byte
Bit No.
Description
Default Value
7
Enable OCD
1 (unprogrammed, OCD disabled)
6
Enable JTAG
0 (programmed, JTAG enabled)
5
Enable SPI Serial Program and
Data Downloading
0 (programmed, SPI prog. enabled)
4
Oscillator options
1 (unprogrammed)
EESAVE
3
EEPROM memory is preserved
through the Chip Erase
1 (unprogrammed, EEPROM not
preserved)
BOOTSZ1
2
for details)
BOOTSZ0
1
for details)
BOOTRST
0
Select reset vector
1 (unprogrammed)