How to do MC68HC912B32 flash Secured? I do not find any flash configure in datasheet.
You cannot find it because there is no added security feature on the HC912B32.
If you need this feature you can look at the 16-bit MCUs:
S12 MagniV® Mixed-Signal MCUs for Automotive and Industrial | NXP
16-bit S12 and S12X MCUs | NXP
I hope it helps.
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