s29gl064m Meet Spansion Inc., s29gl064m Datasheet - Page 76

• Manufacturer Part Number: s29gl064m
• Description: 3.0 Volt-only Page Mode Flash Memory Featuring 0.23 ?m Mirrorbit Process Technolog
• Manufacturer: Meet Spansion Inc.

DQ2: Toggle Bit II
74
Note: The system should recheck the toggle bit even if DQ5 = “1” because the toggle bit may stop toggling as DQ5
changes to “1.” See the subsections on DQ6 and DQ2 for more information.
The “Toggle Bit II” on DQ2, when used with DQ6, indicates whether a particular sector is actively
erasing (that is, the Embedded Erase algorithm is in progress), or whether that sector is erase-
suspended. Toggle Bit II is valid after the rising edge of the final WE# pulse in the command
sequence.
DQ2 toggles when the system reads at addresses within those sectors that are selected for era-
sure. (The system may use either OE# or CE# to control the read cycles.) But DQ2 cannot
distinguish whether the sector is actively erasing or is erase-suspended. DQ6, by comparison, in-
dicates whether the device is actively erasing, or is in Erase Suspend, but cannot distinguish
which sectors are selected for erasure. Thus, both status bits are required for sector and mode
information. Refer to
No
Table 36
Figure 8. Toggle Bit Algorithm
S29GL-M MirrorBit
Complete, Write
Reset Command
Read DQ7–DQ0
Read DQ7–DQ0
Read DQ7–DQ0
Program/Erase
Operation Not
Toggle Bit
Toggle Bit
DQ5 = 1?
= Toggle?
= Toggle?
to compare outputs for DQ2 and DQ6.
START
Twice
Yes
Yes
Yes
D a t a
TM
Flash Family
Operation Complete
No
No
Program/Erase
S h e e t
S29GL-M_00_B8 February 7, 2007