AT29C512
18. Software Data Protection
Enable Algorithm(1)
19. Software Data Protection
Disable Algorithm(1)
LOAD DATA AA
TO
LOAD DATA AA
TO
ADDRESS 5555
ADDRESS 5555
LOAD DATA 55
TO
LOAD DATA 55
TO
ADDRESS 2AAA
ADDRESS 2AAA
LOAD DATA A0
TO
LOAD DATA 80
TO
ADDRESS 5555
WRITES ENABLED
ADDRESS 5555
LOAD DATA
TO
PAGE (128 BYTES)(4)
LOAD DATA AA
TO
ENTER DATA
PROTECT STATE(2)
ADDRESS 5555
LOAD DATA 55
TO
ADDRESS 2AAA
Notes: 1. Data Format: I/O7 - I/O0 (Hex);Address Format: A14
- A0 (Hex).
LOAD DATA 20
TO
2. Data Protect state will be activated at end of program
cycle.
ADDRESS 5555
EXIT DATA
PROTECT STATE(3)
3. Data Protect state will be deactivated at end of pro-
gram period.
LOAD DATA
TO
PAGE (128 BYTES)(4)
4. 128 bytes of data MUST BE loaded.
20. Software Protected Program Cycle Waveform(1)(2)(3)
OE(1)
CE
tWPH
tBLC
tWP
WE
tAS
tAH
tDH
BYTEADDRESS
A0-A6
5555
2AAA
5555
A7-A15(2)
DATA (3)
SECTORADDRESS
tDS
AA
55
A0
BYTE 0
BYTE126
BYTE127
tWC
Notes: 1. A7 through A15 must specify the page address during each high-to-low transition of WE (or CE) after the software code has
been entered.
2. OE must be high when WE and CE are both low.
3. All bytes that are not loaded within the sector being programmed will be indeterminate.
11
0456H–FLASH–2/05
ATMEL [ ATMEL ]
