MBM29DL16XTE/BE70/90
In that case, restart the erase on those sectors and allow them to complete. (Refer to the Write Operation Status
section for Sector Erase Timer operation.) Loading the sector erase buffer may be done in any sequence and
with any number of sectors (0 to 38).
Sector erase does not require the user to program the devices prior to erase. The devices automatically program
all memory locations in the sector(s) to be erased prior to electrical erase (Preprogram function). When erasing
a sector or sectors the remaining unselected sectors are not affected. The system is not required to provide any
controls or timings during these operations.
The system can determine the status of the erase operation by using DQ7 (Data Polling), DQ6 (Toggle Bit), or
RY/BY.
The sector erase begins after the “tTOW” time out from the rising edge of CE or WE whichever happens first for
the last sector erase command pulse and terminates when the data on DQ7 is “1” (See “Write Operation Status”.)
at which time the devices return to the read mode. Data polling and Toggle Bit must be performed at an address
within any of the sectors being erased.
Multiple Sector Erase Time; [Sector Erase Time + Sector Program Time (Preprogramming)] × Number of Sector
Erase
In case of multiple sector erase across bank boundaries, a read from bank (read-while-erase) can not performe.
“(2) Embedded EraseTM Algorithm” in ■FLOW CHART illustrates the Embedded EraseTM Algorithm using typical
command strings and bus operations.
• Erase Suspend/Resume
The Erase Suspend command allows the user to interrupt a Sector Erase operation and then perform data reads
from or programs to a sector not being erased. This command is applicable ONLY during the Sector Erase
operation which includes the time-out period for sector erase. The Erase Suspend command will be ignored if
written during the Chip Erase operation or Embedded Program Algorithm. Writting the Erase Suspend command
(B0h) during the Sector Erase time-out results in immediate termination of the time-out period and suspension
of the erase operation.
Writing the Erase Resume command (30h) resumes the erase operation. The bank addresses of sector being
erasing or suspending should be set when writting the Erase Suspend or Erase Resume command.
When the Erase Suspend command is written during the Sector Erase operation, the device will take a maximum
of “tSPD” to suspend the erase operation. When the devices have entered the erase-suspended mode, the
RY/BY output pin will be at High-Z and the DQ7 bit will be at logic “1”, and DQ6 will stop toggling. The user must
use the address of the erasing sector for reading DQ6 and DQ7 to determine if the erase operation has been
suspended. Further writes of the Erase Suspend command are ignored.
When the erase operation has been suspended, the devices default to the erase-suspend-read mode. Reading
data in this mode is the same as reading from the standard read mode except that the data must be read from
sectors that have not been erase-suspended. Successively reading from the erase-suspended sector while the
device is in the erase-suspend-read mode will cause DQ2 to toggle. (See “DQ2”.)
After entering the erase-suspend-read mode, the user can program the device by writing the appropriate
command sequence for Program. This program mode is known as the erase-suspend-program mode. Again,
programming in this mode is the same as programming in the regular Program mode except that the data must
beprogrammedtosectorsthatarenoterase-suspended. Successivelyreadingfromtheerase-suspendedsector
while the devices are in the erase-suspend-program mode will cause DQ2 to toggle. The end of the erase-
suspended Program operation is detected by the RY/BY output pin, Data polling of DQ7 or by the Toggle Bit I
(DQ6) which is the same as the regular Program operation. Note that DQ7 must be read from the Program address
while DQ6 can be read from any address within bank being erase-suspended.
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SPANSION [ SPANSION ]
