Abov MC96F6332D, User Manual

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MC96F6432
June 22, 2018 Ver. 2.9 323
C. Flash Protection for Invalid Erase/Write
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Overview
This is example to prevent changing code or data in flash by abnormal operation(noise, unstable power,
malfunction, etc…).
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How to protect the flash
•
Divide into decision and execution to Erase/Write in flash.
- Check the program sequence from decision to execution in order of precedence about Erase/Write.
- Setting the flags in program and check the flags in main loop at the end
- When the Flash Erase/Write is executed, check the flags. If not matched, do not execute.
•
Check the range of Flash Sector Address
- If the flash sector address is outside of specific area, do not execute.
•
Use the Dummy Address
- Set the flash sector address to dummy address in usually run time.
- Change the flash sector address to real area range shortly before Erase/Write.
- Even if invalid Erase/Write occurred, it will be Erase/Write in dummy address in flash.
•
Use the LVR/LVI
- Unstable or low powers give an adverse effect on MCU. So use the LVR/LVI