AT28HC256N_14 Datasheet, PDF (9/13 Pages) ATMEL Corporation – Automatic Page Write Operation

AT28HC256N
Software Data Protection
Enable Algorithm⁽¹⁾
LOAD DATA AA
TO
ADDRESS 5555
Software Data Protection Disable
Algorithm⁽¹⁾
LOAD DATA AA
TO
ADDRESS 5555
LOAD DATA 55
TO
ADDRESS 2AAA
LOAD DATA 55
TO
ADDRESS 2AAA
LOAD DATA A0
TO
ADDRESS 5555
WRITES ENABLED⁽²⁾
LOAD DATA XX
TO
ANY ADDRESS⁽⁴⁾
LOAD LAST BYTE
TO
LAST ADDRESS
ENTER DATA
PROTECT STATE
Notes:
1. Data Format: I/O7 - I/O0 (Hex);
Address Format: A14 - A0 (Hex).
2. Write Protect state will be activated at end of write
even if no other data is loaded.
3. Write Protect state will be deactivated at end of
write period even if no other data is loaded.
4. 1 to 64 bytes of data are loaded.
LOAD DATA 80
TO
ADDRESS 5555
LOAD DATA AA
TO
ADDRESS 5555
LOAD DATA 55
TO
ADDRESS 2AAA
LOAD DATA 20
TO
ADDRESS 5555
LOAD DATA XX
TO
ANY ADDRESS⁽⁴⁾
EXIT DATA
PROTECT STATE⁽³⁾
LOAD LAST BYTE
TO
LAST ADDRESS
Software Protected Write Cycle Waveforms⁽¹⁾⁽²⁾
t_WP
t_WPH
t_AS
t_DH
t_AH
t_BLC
t_DS
t_WC
Notes: 1. A6 through A14 must specify the same page address during each high to low transition of WE (or CE) after the software
code has been entered.
2. OE must be high only when WE and CE are both low.
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3446B–PEEPR–4/04