ATTINY2313 Datasheet, PDF (159/211 Pages) ATMEL Corporation – 8-bit AVR Microcontroller with 2K Bytes In-System Programmable Flash

Memory
Programming
Program And Data
Memory Lock Bits
ATtiny2313/V
The ATtiny2313 provides two Lock bits which can be left unprogrammed (“1”) or can be
programmed (“0”) to obtain the additional features listed in Table 66. The Lock bits can
only be erased to “1” with the Chip Erase command.
Table 65. Lock Bit Byte⁽¹⁾
Lock Bit Byte
Bit No
7
6
5
4
3
2
LB2
1
LB1
0
Description
–
–
–
–
–
–
Lock bit
Lock bit
Default Value
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
Note: 1. “1” means unprogrammed, “0” means programmed
Table 66. Lock Bit Protection Modes⁽¹⁾⁽²⁾
Memory Lock Bits
Protection Type
LB Mode
LB2
LB1
1
1
1
No memory lock features enabled.
Further programming of the Flash and EEPROM is
2
1
0
disabled in Parallel and Serial Programming mode. The
Fuse bits are locked in both Serial and Parallel
Programming mode.⁽¹⁾
Further programming and verification of the Flash and
3
0
0
EEPROM is disabled in Parallel and Serial Programming
mode. The Boot Lock bits and Fuse bits are locked in both
Serial and Parallel Programming mode.⁽¹⁾
Notes: 1. Program the Fuse bits and Boot Lock bits before programming the LB1 and LB2.
2. “1” means unprogrammed, “0” means programmed
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