MC9S12HY64 Datasheet, PDF (579/792 Pages) Freescale Semiconductor, Inc – S12 Microcontrollers

48 KByte Flash Module (S12FTMRC48K1V1)
Offset Module Base + 0x0008
7
R
FPOPEN
W
6
RNV6
5
FPHDIS
4
3
FPHS[1:0]
2
FPLDIS
Reset
F
F
F
F
F
F
= Unimplemented or Reserved
Figure 16-13. Flash Protection Register (FPROT)
1
0
FPLS[1:0]
F
F
The (unreserved) bits of the FPROT register are writable with the restriction that the size of the protected
region can only be increased (see Section 16.3.2.9.1, “P-Flash Protection Restrictions,” and Table 16-20).
During the reset sequence, the FPROT register is loaded with the contents of the P-Flash protection byte
in the Flash configuration field at global address 0x3_FF0C located in P-Flash memory (see Table 16-3)
as indicated by reset condition ‘F’ in Figure 16-13. To change the P-Flash protection that will be loaded
during the reset sequence, the upper sector of the P-Flash memory must be unprotected, then the P-Flash
protection byte must be reprogrammed. If a double bit fault is detected while reading the P-Flash phrase
containing the P-Flash protection byte during the reset sequence, the FPOPEN bit will be cleared and
remaining bits in the FPROT register will be set to leave the P-Flash memory fully protected.
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.
Table 16-16. FPROT Field Descriptions
Field
Description
6
Reserved Nonvolatile Bit — The RNV bit should remain in the erased state for future enhancements.
RNV[6]
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
4–3
Flash Protection Higher Address Size — The FPHS bits determine the size of the protected/unprotected area
FPHS[1:0] in P-Flash memory as shown inTable 16-18. The FPHS bits can only be written to while the FPHDIS bit is set.
FPOPEN
1
1
1
1
0
0
0
0
Table 16-17. P-Flash Protection Function
FPHDIS
1
1
0
0
1
1
0
0
FPLDIS
1
0
1
0
1
0
1
0
Function¹
No P-Flash Protection
Protected Low Range
Protected High Range
Protected High and Low Ranges
Full P-Flash Memory Protected
Unprotected Low Range
Unprotected High Range
Unprotected High and Low Ranges
MC9S12HY/HA-Family Reference Manual, Rev. 1.04
Freescale Semiconductor
579