MBM29LV320TE Fujitsu Microelectronics, Inc., MBM29LV320TE Datasheet - Page 29

• Manufacturer Part Number: MBM29LV320TE
• Description: 32 M 4 M X 8/2 M X 16 Bit
• Manufacturer: Fujitsu Microelectronics, Inc.

8.
9.
10. Hidden ROM (Hi-ROM) Program Command
(3) CFI (Common Flash Memory Interface)
(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) . (See “8.
Embedded Program
The CFI (Common Flash Memory Interface) specification outlines device and host system software interrogation
handshake which allows specific vendor-specified software algorithms to be used for entire families of device.
This allows device-independent, JEDEC ID-independent, and forward-and backward-compatible software sup-
port for the specified flash device families. See “Common Flash Memory Interface Code Table” in FLEXIBLE
SECTOR-ERASE ARCHITECTURE for details.
The operation is initiated by writing the query command (98h) into the command register. Following the command
write, a read cycle from specific address retrives device information. Please note that output data of upper byte
(DQ
SECTOR-ERASE ARCHITECTURE. To terminate operation, it is necessary to write the read/reset command
sequence into the register. (See “Common Flash Memory Interface Code Table” in
ERASE ARCHITECTURE.)
The Hi-ROM feature provides a Flash memory region that the system may access through a new command
sequence. This is primarily intended for customers who wish to use an Electronic Serial Number (ESN) in the
device with the ESN protected against modification. Once the Hi-ROM region is protected, any further modifi-
cation of that region is impossible. This ensures the security of the ESN once the product is shipped to the field.
The Hi-ROM region is 256 bytes in length and is stored at the same address of the “outermost” 8 K byte boot
sector. The MBM29LV320TE occupies the address of the byte mode 3FFFC0h to 3FFFFFh (word mode
1FFFE0h to 1FFFFFh) and the MBM29LV320BE type occupies the address of the byte mode 000000h to
000080h (word mode 000000h to 000040h) . After the system has written the Enter Hi-ROM command sequence,
the system may read the Hi-ROM region by using the addresses normally occupied by the boot sector. That is,
the device sends all commands that would normally be sent to the boot sector to the Hi-ROM region. This mode
of operation continues until the system issues the Exit Hi-ROM command sequence, or until power is removed
from the device. On power-up, or following a hardware reset, the device reverts to sending commands to the
boot sector.
The device has a Hidden ROM area with One Time Protect function. This area is to enter the security code and
to unable the change of the code once set. Program/erase is possible in this area until it is protected. However,
once it is protected, it is impossible to unprotect, so please use this with caution.
Hidden ROM area is 256 byte and in the same address area of “outermost” 8 K byte boot block. Therefore, write
the Hidden ROM entry command sequence to enter the Hidden ROM area. It is called as Hidden ROM mode
when the Hidden ROM area appears.
Sector other than the boot block area could be read during Hidden ROM mode. Read/program of the Hidden
ROM area is possible during Hidden ROM mode. Write the Hidden ROM reset command sequence to exit the
Hidden ROM mode.
To program the data to the Hidden ROM area, write the Hidden ROM program command sequence during Hidden
ROM mode. This command is the same as the program command in usual except to write the command during
Hidden ROM mode. Therefore the detection of completion method is the same as in the past, using the DQ
data poling, DQ
other than the Hidden ROM area is selected to program, data of the address will be changed.
Please note that the sector erase command is prohibited during Hidden ROM mode. If the sector erase command
is appeared in this mode, data of the address will be erased.
Hidden ROM (Hi-ROM) Region
Hidden ROM (Hi-ROM) Entry Command
15
to DQ
8
) is “0” in word mode (16 bit) read. See “Common Flash Memory Interface Code Table” in FLEXIBLE
6
toggle bit and RY/BY pin. Need to pay attention to the address to be programmed. If the address
TM
Algorithm for Fast Mode” in FLOW CHART.)
MBM29LV320TE/BE
FLEXIBLE SECTOR-
80/90/10
7
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