Chapter 24 128 KByte Flash Module (S12XFTM128K2V1)
MC9S12XE-Family Reference Manual , Rev. 1.19
856
Freescale Semiconductor
protection byte must be programmed. If a double bit fault is detected while reading the P-Flash phrase
containing the EEE protection byte during the reset sequence, the EPOPEN bit will be cleared and
remaining bits in the EPROT register will be set to leave the buffer RAM EEE partition fully protected.
Trying to write data to any protected area in the buffer RAM EEE partition will result in a protection
violation error and the EPVIOLIF flag will be set in the FERSTAT register. Trying to write data to any
protected area in the buffer RAM partitioned for user access will not be prevented and the EPVIOLIF flag
in the FERSTAT register will not set.
24.3.2.11 Flash Common Command Object Register (FCCOB)
The FCCOB is an array of six words addressed via the CCOBIX index found in the FCCOBIX register.
Byte wide reads and writes are allowed to the FCCOB register.
Table 24-24. EPROT Field Descriptions
Field
Description
7
EPOPEN
Enables writes to the Buffer RAM partitioned for EEE
0 The entire buffer RAM EEE partition is protected from writes
1 Unprotected buffer RAM EEE partition areas are enabled for writes
6–4
RNV[6:4]
Reserved Nonvolatile Bits
— The RNV bits should remain in the erased state for future enhancements
3
EPDIS
Buffer RAM Protection Address Range Disable
— The EPDIS bit determines whether there is a protected
area in a specific region of the buffer RAM EEE partition.
0 Protection enabled
1 Protection disabled
2–0
EPS[2:0]
Buffer RAM Protection Size
— The EPS[2:0] bits determine the size of the protected area in the buffer RAM
EEE partition as shown in
. The EPS bits can only be written to while the EPDIS bit is set.
Table 24-25. Buffer RAM EEE Partition Protection Address Range
EPS[2:0]
Global Address Range
Protected Size
000
0x13_FFC0 – 0x13_FFFF
64 bytes
001
0x13_FF80 – 0x13_FFFF
128 bytes
010
0x13_FF40 – 0x13_FFFF
192 bytes
011
0x13_FF00 – 0x13_FFFF
256 bytes
100
0x13_FEC0 – 0x13_FFFF
320 bytes
101
0x13_FE80 – 0x13_FFFF
384 bytes
110
0x13_FE40 – 0x13_FFFF
448 bytes
111
0x13_FE00 – 0x13_FFFF
512 bytes
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
