Sonic the Hedgehog CD/RAM Editing

From Sonic Retro

SCHG: Sonic the Hedgehog CD
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Editing Art
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RAM Editing
RAM Editing

Main System Memory locations

This is a map of 68k memory as used by the main gameplay engine. For the most part, the memory locations in Sonic CD are the same as they are in the Mega Drive Sonic games. The following are mainly memory locations specific to Sonic CD. Note that any numbers entered (for example, score or number of rings) will have to be converted to hex first.

These are the offsets in RAM.

RAM offset Description
$1512 Ring Counter
$1516 Timer
$151A Score
$152E Time Period. 00 is past, 01 is present, 02 is future
$1548 - $154B X and Y location when time traveling. Used to determine where you spawn.
$156A Good future flag.


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