s29cd-j Meet Spansion Inc., s29cd-j Datasheet - Page 32

• 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.

32
8.7.4
Erase Suspend / Erase Resume Commands
Notes
1. See
2. See
The Erase Suspend command allows the system to interrupt a sector erase operation and then read data
from, or program data to, any sector not selected for erasure. When the Erase Suspend command is written
during the sector erase time-out, the device immediately terminates the time-out period and suspends the
erase operation. The bank address is required when writing this command. This command is valid only during
the sector erase operation, including the minimum 80-µs time-out period during the sector erase command
sequence. The Erase Suspend command is ignored if written during the chip erase operation.
When the Erase Suspend command is written after the 80-µs time-out period has expired and during the
sector erase operation, the device takes 20 µs maximum to suspend the erase operation.
After the erase operation has been suspended, the bank enters the erase-suspend-read mode. The system
can read data from or program data to any sector that is not selected for erasure. (The device “erase
suspends” all sectors selected for erasure.) Note that when the device is in the Erase Suspend mode, the
Reset command is not required for read operations and is ignored.
Further nesting of erase operation is not permitted. Reading at any address within erase suspended sectors
produces status information on DQ7-DQ0. The system can use DQ6 and DQ2 together, to determine if a
sector is actively erasing or is erase-suspended. Refer to Table 8.8 on page 37 for information on these
status bits.
A read operation from the erase-suspended bank returns polling data during the first 8 µs after the erase
suspend command is issued; read operations thereafter return array data. Read operations from the other
bank return array data with no latency.
After an erase-suspended program operation is complete, the bank returns to the erase-suspend read mode.
The system can determine the status of the program operation using the DQ7, DQ6, and/or RY/BY# status
bits, just as in the standard program operation.
To resume the sector erase operation, the system must write the Erase Resume command. The bank
address of the erase-suspended bank is required when writing this command. Further writes of the Resume
command are ignored. Another Erase Suspend command can be written after the chip has resumed erasing.
Section 20.1, Command Definitions on page 72
Section 8.8.6, DQ3: Sector Erase Timer on page 39
S29CD-J & S29CL-J Flash Family
D a t a
No
Figure 8.6 Erase Operation
Command Sequence
Erasure Completed
S h e e t
for erase command sequence.
Write Erase
from System
Data = FFh?
Data Poll
START
for more information.
Yes
( P r e l i m i n a r y )
Embedded
Erase
algorithm
in progress
S29CD-J_CL-J_00_B2 March 7, 2007