Quote from ekeeke:
This has been (finally) added by
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For the record, all CD overlay commands (incl. CUE loop commands) described in MegaSD dev manual (cf. attached file) are supported except the ones that deal with opening/reading files from SD card (starting from command 1Ch) but afaik no MD+ hacks use these commands so far.
As discussed previously, since there is no way to auto-detect a MD+ patched ROM, MegaSD add-on emulation needs to be enabled in core options (through the newly added "CD add-on" option). However, when "CD add-on" option is set to AUTO, if a CUE file with same basename as loaded ROM file is found in same directory AND that CUE file contains MegaSD specific keywords ("REM LOOP xxx", "REM NOLOOP",...), MegaSD CD overlay emulation will be automatically enabled (instead of full Sega/Mega CD hardware emulation).
Additional notes:
- By setting the "CD add-on" option to "SEGA/MEGA CD", you can force Sega/Mega CD hardware emulation when any MD game (<8MB) is loaded even if there is no CUE file found in loaded game directory (this can be useful for demos or homebrew games that want to use Mega CD extra hardware without necessarily having a loaded CD beforehand)
- By setting the "CD add-on" option to "NONE", Sega/Mega CD hardware emulation will be forced disabled, even if a CUE file is found in loaded game directory or when the loaded game is known to have Sega/Mega CD support (like Pier Solar, Flux or Wonder Library). This emulates the behavior where there is no Sega/Mega CD unit attached.
- although no known games are using them, MegaSD extended SSF2 mapper and limited ROM write mapper (automatically enabled when respectively "SEGA SSF2" and "SEGA MEGASD" are found in loaded ROM header) are also emulated, according to the description in MegaSD dev manual . Note that MegaSD overlay will also automatically be enabled when these mappers are detected, no matter of the "CD Add-on" option.
Reference:
MegaSD_DEV_Manual.pdf
