sc9s08mz16 Freescale Semiconductor, Inc, sc9s08mz16 Datasheet - Page 55

• Manufacturer Part Number: sc9s08mz16
• Description: Hcs08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

SEC01:SEC00 changes to 1:0 after successful backdoor key entry or a successful blank check of flash.
4.6.3
Bits 7 through 5 may be read or written at any time. Bits 4 through 0 always read 0 and cannot be written.
Freescale Semiconductor
KEYACC
Reset
Field
5
W
R
Flash Configuration Register (FCNFG)
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
= Unimplemented or Reserved
0
0
6
Figure 4-7. Flash Configuration Register (FCNFG)
SEC01:SEC00
Table 4-10. FCNFG Register Field Descriptions
SC9S08MZ16 MCU Data Sheet, Rev. 0 Draft C
0:0
0:1
1:0
1:1
KEYACC
0
5
Table 4-9. Security States
0
0
4
Description
Section 4.5,
3
0
0
Description
Unsecured
Secure
Secure
Secure
“Security.”
0
0
2
0
0
1
Chapter 4 Memory
0
0
0
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