S912XHZ512F1VAG Datasheet, PDF (145/978 Pages) Freescale Semiconductor, Inc – Covers MC9S12XHZ384, MC9S12XHZ256

Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.3.2.5.1 Flash Protection Restrictions
The general guideline is that Flash protection can only be added and not removed. Table 3-14 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 3-14. 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.
3.3.2.6 Flash Status Register (FSTAT)
The FSTAT register defines the operational status of the module.
Module Base + 0x0005
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 3-12. Flash Status Register (FSTAT — Normal Mode)
Module Base + 0x0005
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 3-13. Flash Status Register (FSTAT — Special Mode)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
145