AS29F400
Preliminary information
®
DATA polling algorithm
Toggle bit algorithm
Read byte (DQ0–DQ7)
Read byte (DQ0–DQ7)
Address = don’t care
Address = VA†
DQ7
=
DQ6
=
YES
NO
DONE
DONE
data
toggle
?
?
NO
YES
DQ5
=
DQ5
NO
NO
=
1
1
?
?
YES
YES
Read byte (DQ0–DQ7)
Address = VA
Read byte (DQ0–DQ7)
Address = don’t care
DQ7
data‡
DQ6
†
YES
NO
=
=
DONE
DONE
†
toggle
?
?
†
NO
FAIL
YES
FAIL
†
‡
VA = Byte address for programming. VA = any of the sector
addresses within the sector being erased during Sector Erase. VA
= valid address equals any non-protected sector group address
during Chip Erase.
†
DQ6 rechecked even if DQ5 = 1 because DQ6 may stop toggling
when DQ5 changes to 1.
DQ7 rechecked even if DQ5 = 1 because DQ5 and DQ7 may not
change simultaneously.
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