MBM29DL34TF Fujitsu Media Devices, MBM29DL34TF Datasheet - Page 30

• Manufacturer Part Number: MBM29DL34TF
• Description: (MBM29DL34BF/TF) FLASH MEMORY CMOS 32 M (4 M X 8/2 M X 16) BIT
• Manufacturer: Fujitsu Media Devices

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MBM29DL34TF/BF
6. Sector Erase
7. Erase Suspend/Resume
to electrical erase (Preprogram function) . 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 DQ
(Toggle Bit II ), or RY/BY output signal. The chip erase begins on the rising edge of the last CE or WE, whichever
happens first from last command sequence and completes when the data on DQ
Status section.) at which time the device returns to read the mode.
Chip Erase Time
“2. Embedded Erase
command strings and bus operations.
Sector erase is a six bus cycle operation. There are two “unlock” write cycles. These are followed by writing the
“set-up” command. Two more “unlock” write cycles are then followed by the Sector Erase command. The sector
address (any address location within the desired sector) is latched on the falling edge of CE or WE whichever
happens later, while the command (Data
After time-out of “t
Multiple sectors may be erased concurrently by writing the six bus cycle operations. This sequence is followed
by writes of the Sector Erase command to addresses in other sectors desired to be concurrently erased. The
time between writes must be less than Erase Time-out time (t
and erasure will start. It is recommended that processor interrupts be disabled during this time to guarantee this
condition. The interrupts can be reoccur after the last Sector Erase command is written. A time-out of “t
the rising edge of last CE or WE, whichever happens first, will initiate the execution of the Sector Erase command
(s) . If another falling edge of CE or WE, whichever happens first occurs within the “t
timer is reset. (Monitor DQ
Erase Timer”.) Resetting the devices once execution has begun will corrupt the data in the sector. In that case,
restart the erase on those sectors and allow them to complete. (Refer to “12. Write Operation Status” 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 using the Embedded Erase algorithm.
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 DQ
RY/BY.
The sector erase begins after the “t
the last sector erase command pulse and completes when the data on DQ
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
In case of multiple sector erase across bank boundaries, a read from bank (read-while-erase) can not perform.
“2. Embedded Erase
command strings and bus operations.
The Erase Suspend command allows the user to interrupt a Sector Erase operation and then perform read or
program to a sector not being erased. This command is applicable ONLY during the Sector Erase operation
within the time-out period for sector erase. Writing 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 writing the Erase Suspend or Erase Resume command.
TOW
Sector Erase Time
” from the rising edge of the last sector erase command, the sector erase operation will begin.
TM
TM
Algorithm” in
Algorithm” in
3
to determine if the sector erase timer window is still open, see “16. DQ
[Sector Erase Time
Sector Erase
TOW
70
” time out from the rising edge of CE or WE whichever happens first for
FLOW CHART illustrates the Embedded Erase
FLOW CHART illustrates the Embedded Erase
All sectors
30h) is latched on the rising edge of CE or WE which happens first.
Chip Program Time (Preprogramming)
Sector Program Time (Preprogramming) ]
TOW
). Otherwise that command will not be accepted
7
7
(Data Polling) , DQ
(Data Polling) , DQ
7
is “1” (See “12. Write Operation
7
is “1” (See Write Operation
TM
TM
TOW
Algorithm using typical
Algorithm using typical
” time-out window the
6
(Toggle Bit) ,DQ
6
(Toggle Bit) , or
Number of
TOW
3
Sector
” from
2