mc9s08ac16 Freescale Semiconductor, Inc, mc9s08ac16 Datasheet - Page 60

• Manufacturer Part Number: mc9s08ac16
• Description: Hcs08 Microcontrollers 8-bit Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

1
Chapter 4 Memory
4.6.4
During reset, the contents of the nonvolatile location NVPROT are copied from FLASH into FPROT. This
register can be read at any time. If FPDIS = 0, protection can be increased, i.e., a smaller value of FPS can
be written. If FPDIS = 1, writes do not change protection.
4.6.5
Bits 3, 1, and 0 always read 0 and writes have no meaning or effect. The remaining five bits are status bits
that can be read at any time. Writes to these bits have special meanings that are discussed in the bit
descriptions.
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Background commands can be used to change the contents of these bits in FPROT.
FPS[7:1]
Reset
Reset
FPDIS
Field
7:1
0
W
W
R
R
FCBEF
FLASH Protection Register (FPROT and NVPROT)
FLASH Status Register (FSTAT)
FLASH Protect Select Bits — When FPDIS = 0, this 7-bit field determines the ending address of unprotected
FLASH locations at the high address end of the FLASH. Protected FLASH locations cannot be erased or
programmed.
FLASH Protection Disable
0 FLASH block specified by FPS[7:1] is block protected (program and erase not allowed).
1 No FLASH block is protected.
1
7
7
= Unimplemented or Reserved
FCCF
1
6
6
This register is loaded from nonvolatile location NVPROT during reset.
Figure 4-8. FLASH Protection Register (FPROT)
Table 4-11. FPROT Register Field Descriptions
Figure 4-9. FLASH Status Register (FSTAT)
FPVIOL
MC9S08AC16 Series Data Sheet, Rev. 0
0
5
5
PRELIMINARY
FACCERR
FPS
0
4
4
(1)
Description
3
3
0
0
FBLANK
0
2
2
Freescale Semiconductor
0
0
1
1
FPDIS
0
0
0
0
(1)