AM29LV160MT90EI Datasheet, PDF (39/63 Pages) SPANSION – 16 Megabit (2 M x 8-Bit/1 M x 16-Bit) MirrorBitTM 3.0 Volt-only Boot Sector Flash Memory

Data Sheet
START
Read DQ7–DQ0
Read DQ7–DQ0 (Note 1)
Toggle Bit
No
= Toggle?
Yes
No
DQ5 = 1?
Yes
Read DQ7–DQ0
Twice
(Notes
1, 2)
Toggle Bit
No
= Toggle?
Yes
Program/Erase
Operation Not
Complete, Write
Reset Command
Program/Erase
Operation Complete
Figure 8. Toggle Bit Algorithm
Notes:
1. Read toggle bit twice to determine whether or not it is toggling. See text.
2. Recheck toggle bit because it may stop toggling as DQ5 changes to “1”. See text.
DQ5: Exceeded Timing Limits
DQ5 indicates whether the program or erase time exceeded a specified internal
pulse count limit. Under these conditions DQ5 produces a “1.” This is a failure
condition that indicates the program or erase cycle was not successfully
completed.
The DQ5 failure condition may appear if the system tries to program a “1” to a
location that is previously programmed to “0.” Only an erase operation can
January 31, 2007 25974B5
Am29LV160M
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