MC9S12GRMV1 Datasheet, PDF (782/1292 Pages) Freescale Semiconductor, Inc – MC9S12G Family Reference Manual and Data Sheet

16 KByte Flash Module (S12FTMRG16K1V1)
The FPROT register, described in Section 24.3.2.9, can be set to protect regions in the Flash memory from
accidental program or erase. Two separate memory regions, one growing downward from global address
0x3_FFFF in the Flash memory (called the higher region), and the remaining addresses in the Flash
memory, can be activated for protection. The Flash memory addresses covered by these protectable regions
are shown in the P-Flash memory map. The higher address region is mainly targeted to hold the boot loader
code since it covers the vector space. Default protection settings as well as security information that allows
the MCU to restrict access to the Flash module are stored in the Flash configuration field as described in
Table 24-4.
Table 24-4. Flash Configuration Field
Global Address
Size
(Bytes)
Description
0x3_FF00-0x3_FF07
0x3_FF08-0x3_FF0B¹
0x3_FF0C¹
0x3_FF0D¹
Backdoor Comparison Key
8
Refer to Section 24.4.6.11, “Verify Backdoor Access Key Command,” and
Section 24.5.1, “Unsecuring the MCU using Backdoor Key Access”
4
Reserved
1
P-Flash Protection byte.
Refer to Section 24.3.2.9, “P-Flash Protection Register (FPROT)”
1
EEPROM Protection byte.
Refer to Section 24.3.2.10, “EEPROM Protection Register (EEPROT)”
0x3_FF0E¹
1
Flash Nonvolatile byte
Refer to Section 24.3.2.16, “Flash Option Register (FOPT)”
0x3_FF0F¹
1
Flash Security byte
Refer to Section 24.3.2.2, “Flash Security Register (FSEC)”
1 _{0x3FF08-0x3_FF0F form a Flash phrase and must be programmed in a single command write sequence. Each byte in}
the 0x3_FF08 - 0x3_FF0B reserved field should be programmed to 0xFF.
P-Flash START = 0x3_C000
Protection
Movable End
0x3_E000
Protection
Fixed End
0x3_F000
0x3_F800
P-Flash END = 0x3_FFFF
Flash Protected/Unprotected Higher Region
2, 4, 8, 16 Kbytes
Flash Configuration Field
16 bytes (0x3_FF00 - 0x3_FF0F)
Figure 24-2. P-Flash Memory Map
MC9S12G Family Reference Manual, Rev.1.23
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Freescale Semiconductor