128 KByte Flash Module (S12FTMRC128K1V1)
13.3 Memory Map and Registers
This section describes the memory map and registers for the Flash module. Read data from unimplemented
memory space in the Flash module is undefined. Write access to unimplemented or reserved memory space
in the Flash module will be ignored by the Flash module.
13.3.1 Module Memory Map
The S12 architecture places the P-Flash memory between global addresses 0x2_0000 and 0x3_FFFF as
shown in Table 13-2.The P-Flash memory map is shown in Figure 13-2.
Table 13-2. P-Flash Memory Addressing
Size
(Bytes)
Global Address
Description
P-Flash Block
0x2_0000 – 0x3_FFFF
128 K
Contains Flash Configuration Field
(see Table 13-3)
The FPROT register, described in Section 13.3.2.9, can be set to protect regions in the Flash memory from
accidental program or erase. Three separate memory regions, one growing upward from global address
0x3_8000 in the Flash memory (called the lower region), 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 13-3.
Table 13-3. Flash Configuration Field
Size
(Bytes)
Global Address
Description
Backdoor Comparison Key
0x3_FF00-0x3_FF07
8
Refer to Section 13.4.5.11, “Verify Backdoor Access Key Command,” and
Section 13.5.1, “Unsecuring the MCU using Backdoor Key Access”
0x3_FF08-0x3_FF0B(1)
0x3_FF0C1
4
1
Reserved
P-Flash Protection byte.
Refer to Section 13.3.2.9, “P-Flash Protection Register (FPROT)”
D-Flash Protection byte.
0x3_FF0D1
0x3_FF0E1
0x3_FF0F1
1
1
1
Refer to Section 13.3.2.10, “D-Flash Protection Register (DFPROT)”
Flash Nonvolatile byte
Refer to Section 13.3.2.16, “Flash Option Register (FOPT)”
Flash Security byte
Refer to Section 13.3.2.2, “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.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
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