MBM29DL32XTE/BE80/90
(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 the
“Extended Sector Group Protection Algorithm” in “■ FLOW CHART”.)
(3) Extended Sector Group Protection
In addition to normal sector group protection, the MBM29DL32XTE/BE has Extended Sector Group Protection
as extended function. This function enable to protect sector group by forcing VID on RESET pin and write a
command sequence. Unlike conventional procedure, it is not necessary to force VID and control timing for control
pins. The only RESET pin requires VID for sector group protection in this mode. The extended sector group
protection requires VID on RESET pin. With this condition, the operation is initiated by writing the set-up command
(60h) into the command register. Then, the sector group addresses pins (A20, A19, A18, A17, A16, A15, A14, A13 and
A12) and (A6, A1, A0) = (0, 1, 0) should be set to the sector group to be protected (recommend to set VIL for the
other addresses pins) , and write extended sector group protection command (60h) . A sector group is typically
protected in 250 µs. To verify programming of the protection circuitry, the sector group addresses pins (A20, A19,
A18, A17, A16, A15, A14, A13 and A12) and (A6, A1, A0) = (0, 1, 0) should be set and write a command (40h) . Following
the command write, a logical “1” at device output DQ0 will produce for protected sector in the read operation. If
the output data is logical “0”, please repeat to write extended sector group protection command (60h) again. To
terminate the operation, it is necessary to set RESET pin to VIH. (Refer to the “Extended Sector Group Protection
Timing Diagram” in “■ TIMING DIAGRAM” and “Extended Sector Group Protection Algorithm” in “■ FLOW
CHART”.)
(4) CFI (Common Flash Memory Interface)
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 devices.
This allows device-independent, JEDEC ID-independent, and forward-and backward-compatible software sup-
port for the specified flash device families. Refer to CFI specification in detail.
The operation is initiated by writing the query command (98h) into the command register. The bank address
should be set when writing this command. Then the device information can be read from the bank, and an actual
data of memory cell be read from the another bank. Following the command write, a read cycle from specific
address retrieves device information. Please note that output data of upper byte (DQ15 to DQ8) is “0” in word
mode (16 bit) read. Refer to the CFI code table. To terminate operation, it is necessary to write the read/reset
command sequence into the register. (See “Common Flash Memory Interface Code” in “■ FLEXIBLE SECTOR-
ERASE ARCHITECTURE”.)
• HiddenROM Region
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 64 Kbytes in length and is stored at the same address of the 8 KB ×8 sectors. The
MBM29DL32XTE occupies the address of the byte mode 3F0000h to 3FFFFFh (word mode 1F8000h to
1FFFFFh) and the MBM29DL32XBE type occupies the address of the byte mode 000000h to 00FFFFh (word
mode 000000h to 007FFFh) . After the system has written the Enter HiddenROM command sequence, the
system may read the HiddenROM region by using the addresses normally occupied by the boot sectors. That
is, the device sends all commands that would normally be sent to the boot sectors 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 sectors.
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SPANSION [ SPANSION ]
