S9S08SL8F1CTJ Datasheet, PDF (59/356 Pages) Freescale Semiconductor, Inc – provides the functional version of the on-chip modules

Chapter 4 Memory
4.5.11.4 FLASH and EEPROM Protection Register (FPROT and NVPROT)
FPROT register defines which FLASH and EEPROM sectors are protected against program and erase
operations.
During the reset sequence, the FPROT register is loaded from the nonvolatile location NVPROT. To
change the protection that will be loaded during the reset sequence, the sector containing NVPROT must
be unprotected and erased, then NVPROT can be reprogrammed.
FPROT bits are readable at any time and writable as long as the size of the protected region is being
increased. Any write to FPROT that attempts to decrease the size of the protected region will be ignored.
Trying to alter data in any protected area will result in a protection violation error and the FPVIOL flag
will be set in the FSTAT register. Mass erase is not possible if any one of the sectors is protected.
7
6
5
4
3
2
1
0
R
EPS
W
FPS
FPOP
Reset
F
F
F
F
F
F
F
F
Field
7:6
EPS
5:1
FPS
0
FPOP
Figure 4-8. FLASH and EEPROM Protection Register (FPROT)
Table 4-11. FPROT Register Field Descriptions
Description
EEPROM Protect Select Bits — This 2-bit field determines the protected EEPROM locations that cannot be
erased or programmed. See Table 4-12.
FLASH Protect Select Bits — This 5-bit field determines the protected FLASH locations that cannot be erased
or programmed. See Table 4-13.
FLASH Protect Open Bit — This bit determines the protected FLASH locations that cannot be erased or
programmed. See Table 4-13.
Table 4-12. EEPROM Block Protection
EPS
0x3
0x2
0x1
0x0
Address Area
Protected
N/A
0x17F8 - 0x17FF
0x17F0 - 0x17FF
0x17E0–0x17FF
Memory Size
Protected (bytes)
0
16
32
64
Number of Sectors
Protected
0
2
4
8
MC9S08EL32 Series and MC9S08SL16 Series Data Sheet, Rev. 3
Freescale Semiconductor
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