Picodrive 1.10, with experimental Sega CD and gmv support

Megadrive emulator for the GP2X

‘After quite a bit of time another peace of code reached usable state. This time it is Sega CD support (well, sort of).

Currently only Sonic CD seems to work. But even that is missing some stuff, like PCM sound and mode7-style graphics emulation in bonus stages. Why would I release this in such unfinished state? I saw the “is Sega CD possible” question too many times, so this is something for you to evaluate and decide for your self. I’m also not sure if there is enough demand for this thing (for me it is good enough, I only need to increase compatibility for all those RPGs to work).

# So what is emulated? another 68k @ 12.5MHz: yes, Cyclone core
# gfx chip, custom ASIC: not yet (faked only)
# PCM sound source: not yet
# CD-ROM controller: yes (mostly)
# bram (internal backup RAM): yes

Not much? It might look like, but it took quite a bit of time to even make the BIOS boot. The work was mostly to read Gens’ asm and recode that stuff in C. This is not a direct port, this is a rewrite, that’s why it is in such unfinished state.

some warnings before you run it:
# sound MUST be set to 44100 stereo, or else cdda music will be played at wrong speeds.
# mp3 decoding is done by ARM940 core, so you must enable “use ARM940 for sound” to get cdda music
# Sonic CD will first complain about unformatted BRAM, you need to press A on BIOS title screen when it says “press start button”, format BRAM and then boot.
# reset option doesn’t work, you must reload ISO to restart
# this version is slightly slower for normal Genesis emulation due to some optimizations temporarily disabled (use 0.964 for Genesis stuff)
# read included readme for more info

list of most wanted games to be emulated
The development is done by loading up a game and seeing what hardware features it is trying to use and then trying to implement them. So I ask you (the community) which games do you want to see emulated next? Maybe somebody can setup a poll or something?
# * Snatcher
# * Shining Force CD (already works if you skip intro?)
# * Lunar: Eternal Blue
# * Lunar 2: The Silver Star
# * Night Trap
# * about a half of all other SegaCD games’

for more info and download click here

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