Chapter 24 128 KByte Flash Module (S12XFTM128K2V1)
MC9S12XE-Family Reference Manual Rev. 1.19
Freescale Semiconductor
855
24.3.2.9.1
P-Flash Protection Restrictions
The general guideline is that P-Flash protection can only be added and not removed.
specifies
all valid transitions between P-Flash protection scenarios. Any attempt to write an invalid scenario to the
FPROT register will be ignored. The contents of the FPROT register reflect the active protection scenario.
See the FPHS and FPLS bit descriptions for additional restrictions.
24.3.2.10 EEE Protection Register (EPROT)
The EPROT register defines which buffer RAM EEE partition areas are protected against writes.
All bits in the EPROT register are readable and writable except for RNV[6:4] which are only readable. The
EPOPEN and EPDIS bits can only be written to the protected state. The EPS bits can be written anytime
until the EPDIS bit is cleared. If the EPOPEN bit is cleared, the state of the EPDIS and EPS bits is
irrelevant.
During the reset sequence, the EPROT register is loaded from the EEE protection byte in the Flash
configuration field at global address 0x7F_FF0D located in P-Flash memory (see
) as indicated
by reset condition F in
. To change the EEE protection that will be loaded during the reset
sequence, the P-Flash sector containing the EEE protection byte must be unprotected, then the EEE
Table 24-23. P-Flash Protection Scenario Transitions
From
Protection
Scenario
To Protection Scenario
(1)
1. Allowed transitions marked with X, see
for a definition of the scenarios.
0
1
2
3
4
5
6
7
0
X
X
X
X
1
X
X
2
X
X
3
X
4
X
X
5
X
X
X
X
6
X
X
X
X
7
X
X
X
X
X
X
X
X
Offset Module Base + 0x0009
7
6
5
4
3
2
1
0
R
EPOPEN
RNV[6:4]
EPDIS
EPS[2:0]
W
Reset
F
F
F
F
F
F
F
F
= Unimplemented or Reserved
Figure 24-15. EEE Protection Register (EPROT)
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:
S12XE
products
in
208
MAPBGA
packages
