512 Kbyte Flash Module (S12XFTX512K4V2)
BookTitle, Rev. 2.4
116 Freescale Semiconductor
2.3.2.5.1 Flash Protection Restrictions
The general guideline is that Flash protection can only be added and not removed. Table 2-15 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.
2.3.2.6 Flash Status Register (FSTAT)
The FSTAT register defines the operational status of the module.
Table 2-15. Flash Protection Scenario Transitions
From
Protection Scenario
To Protection Scenario
1
1 Allowed transitions marked with X.
01234567
0 XXXX
1 XX
2 XX
3 X
4 XX
5 XXXX
6 XXXX
7 XXXXXXXX
Module Base + 0x0005
76543210
R
CBEIF
CCIF
PVIOL ACCERR
0 BLANK 0 0
W
Reset 11000000
= Unimplemented or Reserved
Figure 2-12. Flash Status Register (FSTAT — Normal Mode)
Module Base + 0x0005
76543210
R
CBEIF
CCIF
PVIOL ACCERR
0 BLANK
FAIL
0
W
Reset 11000000
= Unimplemented or Reserved
Figure 2-13. Flash Status Register (FSTAT — Special Mode)