MBM29LV800TE/BE60/70/90
“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. Writting the Erase Suspend command 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 resumes the erase operation. The addresses are DON’T CARES when
writing 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 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 will cause
DQ2 to toggle while the device is in the erase-suspend-read mode (See the section on DQ2) .
After entering the erase-suspend-read mode, the user can program the device by writing the appropriate com-
mand sequence for Program. This program mode is known as the erase-suspend-program mode. Again, pro-
gramming in this mode is the same as programming in the regular Program mode except that the data must be
programmed to sectors that are not erase-suspended. Successively reading from the erase-suspended sector
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.
To resume the operation of Sector Erase, the Resume command (30h) should be written. Any further writes of
the Resume command at this point will be ignored. Another Erase Suspend command can be written after the
chip has resumed erasing.
Extended Command
(1) Fast Mode
MBM29LV800TE/BE have Fast Mode function. This mode dispenses with the initial two unclock cycles required
in the standard program command sequence by writing Fast Mode command into the command register. In this
mode, the required bus cycle for programming is two cycles instead of four bus cycles in standard program
command. In Fast Mode, do not write any command other than the fast program/fast mode reset command. The
read operation is also executed after exiting this mode. To exit this mode, it is necessary to write Fast Mode
Reset command into the command register (Refer to “Embedded Programming Algorithm for Fast Mode” in “■
FLOW CHART”) . The VCC active current is required even CE = VIH during Fast Mode.
(2) Fast Programming
During Fast Mode, the programming can be executed with two bus cycles operation. The Embedded Program
Algorithm is executed by writing program set-up command (A0h) and data write cycles (PA/PD) (Refer to
“Embedded Programming Algorithm for Fast Mode” in “■ FLOW CHART”) .
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