Memory
MCF51CN128 Reference Manual, Rev. 6
4-22
Freescale Semiconductor
Figure 4-3. ColdFire Memory Organization
4.2.1
Flash Module Reserved Memory Locations
Several reserved flash memory locations, shown in
, are used for storing values used by
corresponding peripheral registers. These registers include an 8-byte backdoor key that can be used to gain
access to secure memory resources. During reset events, the contents of the flash protection byte
(NVPROT) and flash nonvolatile byte (NVOPT) in the reserved flash memory are transferred into the
corresponding FPROT and FOPT registers in the high-page register area to control security and block
protection options.
Table 4-4. Reserved Flash Memory Addresses
Address
MSB
1
(0x0)
1
MSB = most significant byte
(0x1)
(0x2)
LSB
2
(0x3)
2
LSB = least significant byte
0x(00)00_03FC
Reserved
FTRIM
(bit 0)
TRIM
0x(00)00_0400
Backdoor comparison key bytes 0–3
byte0
byte1
byte2
byte3
0x(00)00_0404
Backdoor comparison key bytes 4–7
byte4
byte5
byte6
byte7
0x(00)00_0408
Reserved
0x(00)00_040C
Reserved
NVPROT
Reserved
NVOPT
Longword 0x(00)00_0000
Word 0x(00)00_0000
Word 0x(00)00_0002
Byte 0x(00)00_0000
Byte 0x(00)00_0001
Byte 0x(00)00_0002
Byte 0x(00)00_0003
Longword 0x(00)00_0004
Word 0x(00)00_0004
Word 0x(00)00_0006
Byte 0x(00)00_0004
Byte 0x(00)00_0005
Byte 0x(00)00_0006
Byte 0x(00)00_0007
Longword 0x(FF)FF_FFFC
Word 0x(FF)FF_FFFC
Word 0x(FF)FF_FFFE
Byte 0x(FF)FF_FFFC
Byte 0x(FF)FF_FFFD
Byte 0x(FF)FF_FFFE
Byte 0x(FF)FF_FFFF
31
24
23
16 15
8
7
0
...
...
...