zanacandClaude
6266128ce8
Loading a state, and so every RunAhead or netplay rollback, put back an incomplete sound chip or CPU, and the game went on differently from the run that never loaded: the audio of the Mega Drive based boards, Neo Geo and the YM2203 games diverged, and on the 6809 games the game itself. OPN chips (sound/fm.c): - The reset sets the L/R pan of all the channels (0xb4-0xb6) and clears 0x30-0xb2 without storing them in REGS; the postload rewrites REGS, so a channel the game never panned itself was muted after a load (the DAC of the Bare Knuckle games). The reset values are now in REGS (YM2203, YM2608, YM2610, YM2612), and the YM2612 DAC select too. - The postloads of the YM2608 and YM2610 skipped 0xb6 (pan, AMS, PMS of the 3rd channel of each bank), as the YM2612 one did before. - The chip recomputes its phase steps and envelope rates only when a register asks for it, so they can lag behind the registers (e.g. after a 3 slot mode change). They are now saved as they are, with the key codes and the LFO step, instead of being remade from the registers. The YM2612 and YM2610 extra state is one shared block (OPN_EXT), now also used by the YM2203, which had none. - The YM2612 DAC value is saved as it is: before the first write it is 0, which is not what the register gives (aladmdb). - YM2610: the extra FM and SSG state was opt-in (only zn.c asked for it); it is now always saved (Neo Geo). The opt-in FM timers stay as they were. SSG (sound/ay8910.c): the periods of the SSG of a YM chip are saved as they were made; the register rewrite of the postload remade them with the current clock. The YM2203 now saves the SSG extra state too. MultiPCM (sound/multipcm.c): the sample pointer of a voice was remade from the registers at load, without the bank and with the sample number of now, not of the key on; it is saved as its offset in the ROM. The release counter is saved too (Star Wars Arcade). 6809 family: the M6809 did not save the accumulators (D), the HD6309 D and W; the M6809, HD6309 and Konami did not save the cycles of an interrupt taken outside the execute loop. Claude-Session: https://claude.ai/code/session_01N3fzdsnzkQVtgYtYzqepjX Co-authored-by: Claude <[email protected]>
What is MAME 2003-Plus?
MAME 2003-Plus (also referred to as MAME 2003+ and mame2003-plus) is a libretro arcade system emulator core with an emphasis on high performance and broad compatibility with mobile devices, single board computers, embedded systems, and similar platforms.
In order to take advantage of the performance and lower hardware requirements of an earlier MAME architecture, MAME 2003-Plus began with the MAME 2003 codebase which is itself derived from xmame 0.78. Upon that base, MAME 2003-Plus contributors have backported support for an additional 350 games, as well as other functionality not originally present in the underlying codebase.
What games are supported?
View our live compatibility table built using datmagic, a tool created by the MAME 2003-Plus team. Datmagic auto-generates a compatibility table based on the latest XML DAT file. See an incorrect entry? Create a new issue to let us know! This allows us to keep the compatibility table as accurate as possible by fixing it at the source.
Authors: MAMEdev, MAME 2003-Plus team, et al (see LICENSE.md and CHANGELOG.md)
Documentation
User documentation for MAME 2003-Plus can be found in the libretro core documentation library.
Developer documentation can be found in the MAME 2003-Plus wiki.
Development chat
#programming channel of the libretro discord chat server.
Romsets and how to build them for this core
mame2003-plus was originally built from the MAME 0.78 codebase, meaning that 95% or more of MAME 0.78 romsets will work as-is in mame2003-plus, where they immediately benefit from its bugfixes and other improvements. In order to play the new games and games which received ROM updates in mame2003-plus, you will need to find or build the correct romsets.
Read more about rebuilding romsets in the libretro core documentation for mame2003-plus.