M58BW016BB ST Microelectronics, M58BW016BB Datasheet - Page 10

• Manufacturer Part Number: M58BW016BB
• Description: 16 Mbit 512Kb x32 / Boot Block / Burst 3V Supply Flash Memories
• Manufacturer: ST Microelectronics

M58BW016BT, M58BW016BB, M58BW016DT, M58BW016DB
Block Protection
The M58BW016B features four different levels of
block protection. The M58BW016D has the same
block protection with the exception of the Tuning
Block Protection, which is disabled in the factory.
After a device reset the first two kinds of block pro-
tection (WP, RP) can be combined to give a flexi-
ble block protection. They do not affect the Tuning
Block Protection. When the two protections are
disabled, WP and RP at V
the Tuning Block Protection cannot be modified.
All blocks are protected during power-up.
Tuning Block Protection. The
Protection is a software feature to protect certain
10/63
Write Protect Pin, WP, - When WP is low, V
all the lockable parameter blocks (two upper
(Top ) or lower (Bottom)) and all the main blocks
are protected. When WP is high (V
lockable parameter blocks and all the main
blocks are unprotected.
Reset/Power-Down Pin, RP, - If the device is
held in reset mode (RP at V
erase operations can be performed on any
block.
Tuning Block Protection: M58BW016B
features a 64 bit password protection for
program and erase operations for a fixed
number of blocks After power-up or reset the
device is tuning protected. An Unlock command
is provided to allow program or erase operations
in all the blocks.
IH
, the blocks locked by
IL
), no program or
Tuning
IH
) all the
Block
IL
,
blocks from program or erase operations. It allows
the user to lock program and erase operations with
a user definable 64 bit code. It is only available on
the M58BW016B version.
The code is written once in the Tuning Protection
Register and cannot be erased. When shipped the
flash memory will have the Tuning Protection
Code bits set to ‘1'. The user can program a ‘0’ in
any of the 64 positions. Once programmed it is not
possible to reset a bit to ‘1’ as the cells cannot be
erased. The Tuning Protection Register can be
programmed at any moment (after providing the
correct code), however once all bits are set to ‘0’
the Tuning Protection Code can no longer be al-
tered.
The Tuning Protection Code locks the program
and erase operations of 2 parameter and 24 main
blocks, blocks 0, 1 and 15-38 for the bottom con-
figuration and the blocks 0-23, 37 and 38 for the
top configuration.
The tuning blocks are "locked" if the tuning protec-
tion code has not been provided, and “unlocked"
once the correct code has been provided. The tun-
ing blocks are locked after reset or power-up. The
tuning protection status can be monitored in the
Status Register. Refer to the Status Register sec-
tion.
Refer to the Command Interface section for the
Tuning Protection Block Unlock and Tuning Pro-
tection Program commands. See Appendix B, Fig-
ure 25, 26 and 27 for suggested flowcharts for
using the Tuning Block Protection commands. For
further information on the Tuning Block Protection
refer to Application Note, AN1361.