Datasheet

107
ATtiny4/5/9/10 [DATASHEET]
8127F–AVR–02/2013
15.3.1 Non-Volatile Memory Lock Bits
The ATtiny4/5/9/10 provide two Lock Bits, as shown in Table 15-1.
The Lock Bits can be left unprogrammed ("1") or can be programmed ("0") to obtain the additional security shown
in Table 15-2. Lock Bits can be erased to "1" with the Chip Erase command, only.
Notes: 1. Program the configuration section bits before programming NVLB1 and NVLB2.
2. "1" means unprogrammed, "0" means programmed
15.3.2 Flash Memory
The embedded Flash memory of ATtiny4/5/9/10 has four separate sections, as shown in Table 15-3 and Table 15-
3.
Table 15-1. Lock Bit Byte
Lock Bit Bit No Description Default Value
7 1 (unprogrammed)
6 1 (unprogrammed)
5 1 (unprogrammed)
4 1 (unprogrammed)
3 1 (unprogrammed)
2 1 (unprogrammed)
NVLB2 1 Non-Volatile Lock Bit 1 (unprogrammed)
NVLB1 0 Non-Volatile Lock Bit 1 (unprogrammed)
Table 15-2. Lock Bit Protection Modes
Memory Lock Bits
(1)
Protection TypeLock Mode NVLB2
(2)
NVLB1
(2)
1 1 1 No Memory Lock feature Enabled
210
Further Programming of the Flash memory is disabled in
the external programming mode. The configuration
section bits are locked in the external programming
mode
300
Further programming and verification of the flash is
disabled in the external programming mode. The
configuration section bits are locked in the external
programming mode
Table 15-3. Number of Words and Pages in the Flash (ATtiny9/10)
Section Size (Bytes) Page Size (Words) Pages WADDR PADDR
Code (program memory) 1024 8 64 [3:1] [9:4]
Configuration 8 8 1 [3:1] –
Signature
(1)
16 8 2 [3:1] [4:4]
Calibration
(1)
8 8 1 [3:1] –