MC9S12XD256MAL Datasheet, PDF (1119/1348 Pages) Freescale Semiconductor, Inc – Freescale’s Scalable Controller Area Network

Chapter 27 512 Kbyte Flash Module (S12XFTX512K4V2)
27.3.2.5.1 Flash Protection Restrictions
The general guideline is that Flash protection can only be added and not removed. Table 27-15 specifies
all valid transitions between Flash protection scenarios. Any attempt to write an invalid scenario to the
FPROT register will be ignored and the FPROT register will remain unchanged. The contents of the
FPROT register reflect the active protection scenario. See the FPHS and FPLS descriptions for additional
restrictions.
Table 27-15. Flash Protection Scenario Transitions
From
To Protection Scenario¹
Protection Scenario
0
1
2
3
4
5
6
7
0
X
X
X
X
1
X
X
2
X
X
3
X
4
X
X
5
X
X
X
X
6
X
X
X
X
7
X
X
X
X
X
X
X
X
1 Allowed transitions marked with X.
27.3.2.6 Flash Status Register (FSTAT)
The FSTAT register defines the operational status of the module.
7
6
5
4
3
2
1
0
R
CCIF
0
BLANK
0
0
CBEIF
PVIOL
ACCERR
W
Reset
1
1
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 27-12. Flash Status Register (FSTAT — Normal Mode)
7
6
5
4
3
2
1
0
R
CCIF
0
BLANK
0
CBEIF
PVIOL
ACCERR
FAIL
W
Reset
1
1
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 27-13. Flash Status Register (FSTAT — Special Mode)
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MC9S12XDP512 Data Sheet, Rev. 2.21
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