MBM29LV320TE80TN Meet Spansion Inc., MBM29LV320TE80TN Datasheet - Page 32

• Manufacturer Part Number: MBM29LV320TE80TN
• Description: Flash Memory Cmos 32 M 4 M ? 8/2 M ? 16 Bit
• Manufacturer: Meet Spansion Inc.

32
MBM29LV320TE/BE
8.
9.
10. HiddenROM 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. Em-
bedded 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 retrieves 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 ■FLEXIBLE SECTOR-
ERASE ARCHITECTURE.)
The HiddenROM 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 HiddenROM region is protected, any further
modification of that region is impossible. This ensures the security of the ESN once the product is shipped to
the field.
The HiddenROM 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 writes Enter HiddenROM command sequence,
the system can read the HiddenROM 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 HiddenROM region.
This mode of operation continues until the system issues the Exit HiddenROM 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 HiddenROM 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.
HiddenROM area is 256 byte and in the same address area of “outermost” 8 K byte boot block. Therefore, write
the HiddenROM entry command sequence to enter the HiddenROM area. It is called as HiddenROM mode
when the HiddenROM area appears.
Sector other than the boot block area could be read during HiddenROM mode. Read/Program of the HiddenROM
area is possible during HiddenROM mode. Write the HiddenROM reset command sequence to exit the Hidden-
ROM mode.
To program the data to the HiddenROM area, write the HiddenROM program command sequence during Hid-
denROM mode. This command is the same as the program command in usual except to write the command
during HiddenROM mode. Therefore the detection of completion method is the same as, using the DQ
poling, DQ
other than the HiddenROM area is selected to program, data of the address will be changed.
HiddenROM Region
HiddenROM Entry Command
15
to DQ
6
8
toggle bit and RY/BY pin. Need to pay attention to the address to be programmed. If the address
) is “0” in word mode (16 bit) read. See “Common Flash Memory Interface Code Table” in ■FLEXIBLE
TM
Algorithm for Fast Mode” in ■FLOW CHART.)
Retired Product DS05-20894-5E_July 31, 2007
80/90/10
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data