30 SBC330 3U VPX Single Board Computer
Publication No. SBC330-0HH/3
5.3.7 Flash Sector protection
The
SBC330
uses
Spansion
S29GLxxGP
Flash
devices,
which
provide
advanced
methods
of
sector
protection
to
ensure
the
integrity
of
code
data
contained
in
the
Flash
array.
Protection
is
defined
on
a
per
‐
sector
basis,
where
a
sector
is
256 KBytes
(0x40000)
in
size.
Locked
sectors
cannot
be
erased
or
programmed;
they
may
only
be
read.
Only
the
boot
area
of
Flash
is
protected
by
a
hardware
jumper.
Software
must
be
used
to
configure
the
Flash
devices
to
protect
against
corruption
of
Flash
data.
The
following
types
of
protection
are
provided:
• Persistent
sector
protection
provides
non
‐
volatile
protection
that
remains
in
place
when
a
board
is
power
cycled
or
reset.
Each
Flash
sector
may
be
set
to
be
locked
(write
‐
protected)
or
unlocked
(write
‐
enabled)
by
writing
to
configuration
registers
within
the
Flash.
The
configuration
of
this
protection
is
only
possible
when
the
Flash
(password)
Protection
Unlock
Link
(P10
pins
1
and
2)
is
fitted.
If
this
link
is
not
fitted,
the
software
is
unable
to
change
the
sector
protection
and
those
sectors
that
are
locked
may
not
be
erased
or
reprogrammed
under
any
circumstances.
• Non
‐
persistent
protection
may
also
be
used.
This
protection
is
only
present
until
a
power
cycle
or
hardware
reset
occurs
and
may
be
modified
by
user
software.
NOTE
Sectors that are locked using the Persistent mode may not be unlocked using this mechanism.
NOTE
Do not rely on non-persistent protection, as it may be subsequently altered by software. If further
protection is required, use the Persistent protection method.
For
further
details
of
the
protection
mechanisms,
refer
to
the
Spansion
S29GL01Pxxx
data
sheets.
Table 5-5
Address
256 MBytes of Flash
512 MBytes of Flash
FFFF FFFF
Boot
Boot
FF80 0000
Page 1 (248 MBytes)
(Default Page (1) pointer)
Page 1 (248 MBytes)
E000 0000
CS1 or CS3
Page 0 (256 MBytes)
(Page 0 bit set in Flash_CTRL
Register)
CS1 or CS3
Errata
May
2011