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MiSTer-devel / TurboGrafx16_MiSTer

TurboGrafx-16 CD / PC Engine CD for MiSTer
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Backup RAM unlock (bit 7 of $1807) should also be able to re-lock backup memory #201

Closed dshadoff closed 10 months ago

dshadoff commented 10 months ago

Writing a '1' to bit 7 (value $80) to CD status register at $1807 unlocks the Backup RAM - this is implemented correctly. However, writing a '0' to the same bit should lock the Backup RAM again (not implemented).

Currently, reading from $1803 locks the Backup RAM - this is the "normal" technique to lock Backup RAM - but the write to $1807 should also work.

dshadoff commented 10 months ago

Closing, as the new release (Dec 4, 2023) includes this fix.