MBM29F160BE-55 FUJITSU [Fujitsu Component Limited.], MBM29F160BE-55 Datasheet - Page 14

• Manufacturer Part Number: MBM29F160BE-55
• Description: 16M (2M X 8/1M X 16) BIT
• Manufacturer: FUJITSU [Fujitsu Component Limited.]

MBM29F160TE
Write
Write Protect (WP)
Sector Protection
Temporary Sector Unprotection
14
Device erasure and programming are accomplished via the command register. The command 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 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 CE or WE, whichever occurs later, while data is latched on the rising edge of CE or WE pulse,
whichever occurs first. Standard microprocessor write timings are used.
Refer to AC Write Characteristics and the Erase/Programming Waveforms for specific timing parameters.
The write Protect function provides a hardware method of protecting certain boot sectors without using V
If the system asserts V
byte boot sectors independently of whether this sector was protected or unprotected using the method described
in "Sector / Sector Block Protection and Unprotection". The outmost 16K byte boot sector is the sector containing
the lowest addresses in a bottom-boot-configured devices, or the sector containing the highest addresses in a
top-boot-configured device.
If the system asserts V
last set to be protected or unprotected. That is, sector protection or unprotection for this sector depends on
whether it was last protected or unprotected using the method describe in "Sector / Sector Block Protection and
Unprotection".
The MBM29F160TE/BE features hardware sector protection. This feature will disable both program and erase
operations in any number of sectors (0 through 34). The sector protection feature is enabled using programming
equipment at the user’s site. The device is shipped with all sectors unprotected.
To activate this mode, the programming equipment must force V
V
to the sector to be protected. Tables 5 and 6 define the sector address for each of the thirty five (35) 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 figures 16
and 24 for sector protection waveforms and algorithm.
To verify programming of the protection circuitry, the programming equipment must force V
with CE and OE at V
while (A
the devices will read 00H for unprotected sector. In this mode, the lower order addresses, except for A
A
codes. 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 pins (A
A
Tables 4.1 and 4.2 for Autoselect codes.
This feature allows temporary unprotection of previously protected sectors of the MBM29F160TE/BE devices
in order to change data. The Sector Unprotection mode is activated by setting the RESET pin to high voltage
(12 V). During this mode, formerly protected sectors can be programmed or erased by selecting the sector
addresses. Once the 12 V is taken away from the RESET pin, all the previously protected sectors will be protected
again. Refer to Figures 18 and 25.
ID
6
14
are DON’T CARES. Address locations with A
, A
= 11.5V), CE = V
13
, and A
6
, A
-1
requires to apply to V
1
, A
12
0
) = (0, 1, 0) will produce a logical “1” code at device output DQ
) represents the sector address will produce a logical “1” at DQ
IL
IL
, and A
IL
and WE at V
IH
on the WP pin, the device disables program and erase functions in the "outermost" 16K
on the WP pin, the devices reverts to whether the outmost 16K byte boot sector was
6
= V
-55/-70/-90
IL
IL
. The sector addresses (A
in byte mode.
IH
. Scanning the sector addresses (A
/MBM29F160BE
IL
1
, while CE is at V
= V
IL
are reserved for Autoselect manufacturer and device
19
, A
ID
18
on address pin A
, A
IL
and OE is at V
17
, A
19
16
, A
, A
0
18
15
for a protected sector. Otherwise
, A
, A
0
for a protected sector. See
9
17
14
IH
and control pin OE, (suggest
, A
, A
. Addresses are latched on
-55/-70/-90
13
16
, and A
, A
15
ID
19
, A
on address pin A
, A
12
14
18
) should be set
, A
, A
13
17
, and A
0
, A
, A
16
1
, and
, A
ID
.
12
15
)
9
,