S29WS-P Datasheet, PDF (40/89 Pages) SPANSION – 512/256/128 Mb (32/16/8 M x 16 bit) 1.8 V Burst Simultaneous Read/Write MirrorBit Flash Memory

Data Sheet (Advance Information)
7.7.6
Erase Suspend/Erase Resume Commands
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 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. The bank address is required when writing this command. This command is valid only
during the sector erase operation, including the minimum t_SEA 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 t_SEA time-out period has expired and during the sector
erase operation, the device requires a minimum of t_ESL (erase suspend latency) 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 not selected for erasure. (The device erase suspends all
sectors selected for erasure.) Reading at any address within erase-suspended sectors produces status
information on DQ7-DQ0. The system can use DQ7, or DQ6, and DQ2 together, to determine if a sector is
actively erasing or is erase-suspended. Refer to Table 7.36 on page 45 for information on these status bits.
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 or DQ6 status bits, just as in
the standard program operation.
Note: While an erase operation can be suspended and resumed multiple times, a minimum delay of t_ERS
(Erase Resume to Suspend) is required from resume to the next suspend.
In the erase-suspend-read mode, the system can also issue the Autoselect command sequence. Refer to
Write Buffer Programming on page 30 and Autoselect on page 26 for details.
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.
Software Functions and Sample Code
Table 7.30 Erase Suspend
(LLD Function = lld_EraseSuspendCmd)
Cycle
1
Operation
Write
Byte Address
Bank Address
Word Address
Bank Address
Data
00B0h
The following is a C source code example of using the erase suspend function. Refer to the Spansion Low
Level Driver User’s Guide (available on www.spansion.com) for general information on Spansion Flash
memory software development guidelines.
/* Example: Erase suspend command */
*( (UINT16 *)bank_addr + 0x000 ) = 0x00B0; /* write suspend command
*/
Cycle
1
Operation
Write
Table 7.31 Erase Resume
(LLD Function = lld_EraseResumeCmd)
Byte Address
Bank Address
Word Address
Bank Address
Data
0030h
The following is a C source code example of using the erase resume function. Refer to the Spansion Low
Level Driver User’s Guide (available on www.spansion.com) for general information on Spansion Flash
memory software development guidelines.
/* Example: Erase resume command */
*( (UINT16 *)bank_addr + 0x000 ) = 0x0030; /* write resume command
*/
/* The flash needs adequate time in the resume state */
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S29WS-P
S29WS-P_00_A7 November 8, 2006