mc9s08sh8mwjr Freescale Semiconductor, Inc, mc9s08sh8mwjr Datasheet - Page 56

• Manufacturer Part Number: mc9s08sh8mwjr
• Description: S08sh 5-volt 8-bit Microcontrollers With Sci, Spi, I2c, Adc And Analog Comparators
• Manufacturer: Freescale Semiconductor, Inc

1
Chapter 4 Memory
4.7.3
4.7.4
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 (that is, a smaller value of FPS
can be written). If FPDIS = 1, writes do not change protection.
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Background commands can be used to change the contents of these bits in FPROT.
KEYACC
Reset
Reset
Field
5
W
W
R
R
FLASH Configuration Register (FCNFG)
FLASH Protection Register (FPROT and NVPROT)
Enable Writing of Access Key — This bit enables writing of the backdoor comparison key. For more detailed
information about the backdoor key mechanism, refer to
0 Writes to 0xFFB0–0xFFB7 are interpreted as the start of a FLASH programming or erase command.
1 Writes to NVBACKKEY (0xFFB0–0xFFB7) are interpreted as comparison key writes.
0
0
7
7
= Unimplemented or Reserved
0
0
6
6
Figure 4-7. FLASH Configuration Register (FCNFG)
1
This register is loaded from nonvolatile location NVPROT during reset.
Figure 4-8. FLASH Protection Register (FPROT)
Table 4-10. FCNFG Register Field Descriptions
SEC01:SEC00 changes to 1:0 after successful backdoor
key entry or a successful blank check of FLASH.
SEC01:SEC00
KEYACC
MC9S08SH32 Series Data Sheet, Rev. 2
0
5
5
0:0
0:1
1:0
1:1
Table 4-9. Security States
PRELIMINARY
FPS
0
0
4
4
(1)
Description
Section 4.6,
Description
unsecured
secure
secure
secure
3
0
0
3
1
“Security.”
0
0
2
2
Freescale Semiconductor
0
0
1
1
FPDIS
0
0
0
0
(1)