MBM29QM12DH Fujitsu Microelectronics, Inc., MBM29QM12DH Datasheet - Page 34

• Manufacturer Part Number: MBM29QM12DH
• Description: Page Mode Flash Memory 128m 8m X 16 Bit
• Manufacturer: Fujitsu Microelectronics, Inc.

Word Programming Command
Program Suspend/Resume Command
To terminate the operation, it is necessary to write the Read/Reset command sequence into the register. To
execute the Autoselect command during the operation, Read/Reset command sequence must be written before
the Autoselect command.
The device is programmed on a word-by-word basis. Programming is a four bus cycle operation. There are two
“unlock” write cycles. These are followed by the program set-up command and data write cycles. Addresses are
latched on the falling edge of CE or WE, whichever happens later, and the data is latched on the rising edge of
CE or WE, whichever happens first. The rising edge of CE or WE (whichever happens first) starts programming.
Upon executing the Embedded Program Algorithm command sequence, the system is not required to provide
further controls or timings. The device will automatically provide adequate internally generated program pulses
and verify the programmed cell margin.
The system can determine the status of the program operation by using DQ
or RY/BY. The Data Polling and Toggle Bit must be performed at the memory location which is being programmed.
The automatic programming operation is completed when the data on DQ
bit at which time the device returns to the read mode and addresses are no longer latched (see “Hardware
Sequence Flags Table” in “ COMMAND DEFINITION”). Therefore, the device requires that a valid address to
the device be supplied by the system in this particular instance. Hence, Data Polling must be performed at the
memory location which is being programmed.
Programming is allowed in any sequence and across sector boundaries. Beware that a data “0” cannot be
programmed back to a “1”. Attempting to do so may either hang up the device or result in an apparent success
according to the data polling algorithm but a read from Read/Reset mode will show that the data is still “0”. Only
erase operations can convert from “0”s to “1”s.
“Embedded Erase
command strings and bus operations.
The Program Suspend command allows the system to interrupt a program operation so that data can be read
from any address. Writing the Program Suspend command (B0h) during the Embedded Program operation
immediately suspends the programming. The Program Suspend command may also be issued during a pro-
gramming operation while an erase is suspended. The bank addresses of sector being programmed should be
set when writing the Program Suspend command.
When the Program Suspend command is written during a programming process, the device halts the program
operation within 1 µs and updates the status bits.
After the program operation has been suspended, the system can read data from any address. The data at
program-suspended address is not valid. Normal read timing and command definitions apply.
After the Program Resume command (30h) is written, the device reverts to programming. The bank addresses
of sectors being suspended should be set when writing the Program Resume command. The system can
determine the status of the program operation using the DQ
operation. See “Write Operation Status” for more information.
The system may also write the Autoselect command sequence when the device in the Program Suspend mode.
The device allows reading Autoselect codes at the addresses within programming sectors, since the codes are
not stored in the memory. When the device exits the Autoselect mode, the device reverts to the Program Suspend
mode, and is ready for another valid operation. See “Autoselect Command Sequence” for more information.
The system must write the Program Resume command (address bits are “Bank Address”) to exit from the
Program Suspend mode and continue the programming operation. Further writes of the Resume command are
ignored. Another Program Suspend command can be written after the device has resumed programming.
If hardware reset occurs during the programming operation, the data being written is not guaranteed.
TM
Algorithm” in “ FLOW CHART” illustrates the Embedded Program
7
or DQ
6
status bits, just as in the standard program
MBM29QM12DH
7
is equivalent to data written to this
7
(Data Polling) , DQ
TM
Algorithm using typical
6
(Toggle Bit)
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