MBM29LV800TE Fujitsu Microelectronics, Inc., MBM29LV800TE Datasheet - Page 18

• Manufacturer Part Number: MBM29LV800TE
• Description: 8m 1m X 8/512 K X 16 Bit
• Manufacturer: Fujitsu Microelectronics, Inc.

Write
Sector Protection
Temporary Sector Unprotection
Word 0 (A
code (MBM29LV800TE
MBM29LV800BE
Protection Verify Autoselect Codes” and “Expanded Autoselect Code Table” in “
All identifiers for manufactures and device will exhibit odd parity with DQ
read the proper device codes when executing the autoselect, A
Protection Verify Autoselect Codes” and “Expanded Autoselect Code Table” in “
Device erasure and programming are accomplished via the command register. The contents of the register serve
as inputs to the internal state machine. The state machine outputs dictate the function of the device.
The command register itself does not occupy any addressable memory location. The register is a latch used to
store the commands, along with the address and data information needed to execute the command. The
command register is written by bringing WE to V
the falling edge of WE or CE, whichever happens later; while data is latched on the rising edge of WE or CE,
whichever happens first. Standard microprocessor write timings are used.
Refer to AC Write Characteristics and the Erase/Programming Waveforms for specific timing parameters.
The MBM29LV800TE/BE feature hardware sector protection. This feature will disable both program and erase
operations in any number of sectors (0 through 18) . The sector protection feature is enabled using programming
equipment at the user’s site. The devices are shipped with all sectors unprotected. Alternatively, Fujitsu may
program and protect sectors in the factory prior to shiping the device.
To activate this mode, the programming equipment must force V
V
the sector to be protected. “Sector Address Tables (MBM29LV800TE)” and “Sector Address Tables
(MBM29LV800BE) ” in “
of the nineteen (19) individual sectors. Programming of the protection circuitry begins on the falling edge of the
WE pulse and is terminated with the rising edge of the same. Sector addresses must be held constant during
the WE pulse. See “Sector Protection Timing Diagram” in “
rithm” in “
To verify programming of the protection circuitry, the programming equipment must force V
with CE and OE at V
(A
devices will read 00h for unprotected sector. In this mode, the lower order addresses, except for A
are DON’T CARES. Address locations with A
A
It is also possible to determine if a sector is protected in the system by writing an Autoselect command. Performing
a read operation at the address location XX02h, where the higher order addresses (A
and A
“MBM29LV800TE/BE Sector Protection Verify Autoselect Codes” and “Expanded Autoselect Code Table” in
“
This feature allows temporary unprotection of previously protected sectors of the MBM29LV800TE/BE devices
in order to change data. The Sector Unprotection mode is activated by setting the RESET pin to high voltage
(V
addresses. Once the V
again. See “Temporary Sector Unprotection Timing Diagram” in “
Unprotection Algorithm” in “
ID
-1
6
ID
, A
requires to apply to V
) . During this mode, formerly protected sectors can be programmed or erased by selecting the sector
DEVICE BUS OPERATION” for Autoselect codes.
11.5 V) , CE
1
, A
12
) are the desired sector address will produce a logical “1” at DQ
0
0
)
FLOW CHART” for sector protection waveforms and algorithm.
V
IL
(0, 1, 0) will produce a logical “1” code at device output DQ
) represents the manufacturer’s code (Fujitsu 04h) and (A
225Bh for
V
IL
IL
and WE at V
, and A
ID
is taken away from the RESET pin, all the previously protected sectors will be protected
IL
DAh and MBM29LV800BE
on byte mode.
FLEXIBLE SECTOR-ERASE ARCHITECTURE” define the sector address for each
6
FLOW CHART”.
16 mode) . These two bytes/words are given in “MBM29LV800TE/BE Sector
V
IL
IH
. The sector addresses (A
. Scanning the sector addresses (A
1
V
IL
, while CE is at V
IL
are reserved for Autoselect manufacturer and device codes.
5Bh for
MBM29LV800TE/BE
TIMING DIAGRAM” and “Sector Protection Algo-
18
1
ID
, A
must be V
on address pin A
8 mode; MBM29LV800TE
17
IL
TIMING DIAGRAM” and “Temporary Sector
, A
and OE is at V
16
, A
18
0
0
7
IL
, A
for a protected sector. Otherwise the
15
. (See “MBM29LV800TE/BE Sector
defined as the parity bit. In order to
V
, A
17
IH
, A
14
) represents the device identifier
0
, A
DEVICE BUS OPERATION”.)
9
16
for a protected sector. See
DEVICE BUS OPERATION”.
and control pin OE, (suggest
IH
, A
13
. Addresses are latched on
, and A
15
18
, A
, A
14
ID
, A
17
12
, A
on address pin A
22DAh and
) should be set to
13
, and A
16
, A
0
, A
15
60/70/90
, A
1
12
, and A
) while
14
, A
13
9
6
,
17