Freescale Semiconductor TWR-S12G64 Scalable Platform for Automotive Applications TWR-S12G64-KIT TWR-S12G64-KIT Data Sheet
Product codes
TWR-S12G64-KIT
16 KByte Flash Module (S12FTMRG16K1V1)
MC9S12G Family Reference Manual,
Rev.1.23
796
Freescale Semiconductor
Trying to alter data in any protected area in the P-Flash memory will result in a protection violation error
and the FPVIOL bit will be set in the FSTAT register. The block erase of a P-Flash block is not possible if
any of the P-Flash sectors contained in the same P-Flash block are protected.
and the FPVIOL bit will be set in the FSTAT register. The block erase of a P-Flash block is not possible if
any of the P-Flash sectors contained in the same P-Flash block are protected.
Although the protection scheme is loaded from the Flash memory at global address 0x3_FF0C during the
reset sequence, it can be changed by the user. The P-Flash protection scheme can be used by applications
requiring reprogramming in single chip mode while providing as much protection as possible if
reprogramming is not required.
reset sequence, it can be changed by the user. The P-Flash protection scheme can be used by applications
requiring reprogramming in single chip mode while providing as much protection as possible if
reprogramming is not required.
Table 24-17. FPROT Field Descriptions
Field
Description
7
FPOPEN
Flash Protection Operation Enable — The FPOPEN bit determines the protection function for program or
erase operations as shown in
erase operations as shown in
for the P-Flash block.
0 When FPOPEN is clear, the FPHDIS bit defines an unprotected address range as specified by the FPHS bits
1 When FPOPEN is set, the FPHDIS bit enables protection for the address range specified by the FPHS bits
1 When FPOPEN is set, the FPHDIS bit enables protection for the address range specified by the FPHS bits
6
RNV[6]
Reserved Nonvolatile Bit — The RNV bit should remain in the erased state for future enhancements.
5
FPHDIS
Flash Protection Higher Address Range Disable — The FPHDIS bit determines whether there is a
protected/unprotected area in a specific region of the P-Flash memory ending with global address 0x3_FFFF.
0 Protection/Unprotection enabled
1 Protection/Unprotection disabled
protected/unprotected area in a specific region of the P-Flash memory ending with global address 0x3_FFFF.
0 Protection/Unprotection enabled
1 Protection/Unprotection disabled
4–3
FPHS[1:0]
Flash Protection Higher Address Size — The FPHS bits determine the size of the protected/unprotected area
in P-Flash memory as shown in
in P-Flash memory as shown in
. The FPHS bits can only be written to while the FPHDIS bit is set.
2–0
RNV[2:0]
Reserved Nonvolatile Bits — These RNV bits should remain in the erased state.
Table 24-18. P-Flash Protection Function
FPOPEN
FPHDIS
Function
1
1
For range sizes, refer to
1
1
No P-Flash Protection
1
0
Protected High Range
0
1
Full P-Flash Memory Protected
0
0
Unprotected High Range
Table 24-19. P-Flash Protection Higher Address Range
FPHS[1:0]
Global Address Range
Protected Size
00
0x3_F800–0x3_FFFF
2 Kbytes
01
0x3_F000–0x3_FFFF
4 Kbytes
10
0x3_E000–0x3_FFFF
8 Kbytes
11
0x3_C000–0x3_FFFF
16 Kbytes