s29cd-j Meet Spansion Inc., s29cd-j Datasheet - Page 38

• Manufacturer Part Number: s29cd-j
• Description: 32/16 Megabit Cmos 2.6 Volt Or 3.3 Volt-only Simultaneous Read/write, Dual Boot, Burst Mode Flash Memory With Versatilei/o?
• Manufacturer: Meet Spansion Inc.

38
8.8.5
DQ5: Exceeded Timing Limits
Notes
1. Read toggle bit with two immediately consecutive reads to determine whether or not it is toggling.
2. Recheck toggle bit because it may stop toggling as DQ5 changes to 1.
DQ5 indicates whether the program or erase time has 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 change a 0 back to a 1. Under this condition, the device halts
the operation, and when the operation has exceeded the timing limits, DQ5 produces a 1.
Under both these conditions, the system issues the reset command to return the device to reading array data.
(Note 1)
S29CD-J & S29CL-J Flash Family
No
D a t a
Figure 8.8 Toggle Bit Algorithm
Read Byte Twice
DQ6 = Toggle?
DQ6 = Toggle?
Adrdess = VA
S h e e t
Address = VA
Address = VA
(DQ0-DQ7)
(DQ0-DQ7)
(DQ0-DQ7)
Read Byte
Read Byte
DQ5 = 1?
START
FAIL
Yes
Yes
Yes
( P r e l i m i n a r y )
(Notes 1, 2)
No
No
PASS
S29CD-J_CL-J_00_B2 March 7, 2007