Todo/Mysteries: Difference between revisions

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Rename palette ram bus in [[NEO-G0]] by PC0~PC15 (see schematics page 3).
==Housekeeping==
* Merge Sprite_scaling with Sprite_shrinking
* Rename GPU to VDC everywhere ? Or VDP ? LSPC isn't really a processor. Sorry :/
* Rename BIOS to system ROM everywhere (done ?)
* Use 3rd parameter of Sig template (signal polarity)
* Use Chipname, Reg, Sig, BR templates


==Official SNK doc infos==
==Useful==
* Tooltip extension for registers ?
* Check everything in [[Meg count]]. Add links to game pages.
* Add pin numbers on [[AES cartridge pinout]]
* Add on to [[How to start]] page
* Tutorials
* Change DEFINE names (and register names ?) to the ones used in the AoF source code
* Memory chip pinouts
* Finish PRO chipset pinouts !
* M1 and S1 ROM speeds
* CD I/O ERROR 0001 0002 0003 ?
* CRC32 of all known ROMs/ISOs from MAME's neogeo.inc
* Add more jumper configs
* Memory card stuff (format, banks...)
* neo-mga on mv1a + PALs info
* Chip functions for each kind of board (even discrete logic)
* NEOGEO chip sizes, like pitch, span and body (useful for finding drop-in replacements like CPLD or Castellated pcb boards with replacement chips)


*First 80 bytes of code are switchable through REG_SWPBIOS/REG_SWPROM and switched to the BIOS part on startup ($0~$7F = $C00000~$C0007F)
==Trivia==
* Add links to TCRF pages for the debug DIPs of each game
* CMC fix bankswitching: how/when is vram bank info sent to the cartridge?
* Recent security chips info (SMA, PVC...)
* Neo cd chip pinouts (not very useful)
* Are the two missing FM channels from the YM2610 actually off the die or just disabled?


==Registers==
==Analysis / mysteries==
*What are $380011, $380061, $380065, $380067, and $3800E1 used for ?
* Why does the L0 ROM need an output buffer ?
* Loading time graphs for all CD games, is MESS reliable enough ? (no)
* Details on CD registers
* CDDA playback (needs more research in CD system rom)
* Dump LC98000 version Neo CD system rom
* [[LC8953]]/98000 microcode (note: Sanyo tech support has nothing left except publicly available brief sheet)


SP-E init code:
==Verify==
<pre>
* Check [[Clock]] distribution diagram, especially on cart edge
move.b d0,$380065
move.b d0,$380067
</pre>
 
*CD registers
 
==Others==
 
*Fix banking with NEO-CMC:
<pre>
284      if (banked && state->m_fixed_layer_bank_type == 1)
  285      {
  286          int garoubank = 0;
  287          int k = 0;
  288          int y = 0;
  289          while (y < 32)
  290          {
  291              if (state->m_videoram[0x7500 + k] == 0x0200 && (state->m_videoram[0x7580 + k] & 0xff00) == 0xff00)
  292              {
  293                  garoubank = state->m_videoram[0x7580 + k] & 3;
  294                  garouoffsets[y++] = garoubank;
  295              }
  296              garouoffsets[y++] = garoubank;
  297              k += 2;
  298          }
  299      }
</pre>
*neo-mga on mv1a + PALs, neo-sdr and neo-dcr info
*CDDA playback (needs more research in cd bios)
*neo cd schematics
*dump lc98000 version neocd bios
*fix bankswitching in neo-cmc
*lspc-a0, pro-b0 and pro-c0 pinouts
*[[How to start]] page
*[[LC8953]] microcode
*How does the [[Mahjong controller]] works ? (SNK doc)

Latest revision as of 10:48, 22 May 2020

Housekeeping

  • Merge Sprite_scaling with Sprite_shrinking
  • Rename GPU to VDC everywhere ? Or VDP ? LSPC isn't really a processor. Sorry :/
  • Rename BIOS to system ROM everywhere (done ?)
  • Use 3rd parameter of Sig template (signal polarity)
  • Use Chipname, Reg, Sig, BR templates

Useful

  • Tooltip extension for registers ?
  • Check everything in Meg count. Add links to game pages.
  • Add pin numbers on AES cartridge pinout
  • Add on to How to start page
  • Tutorials
  • Change DEFINE names (and register names ?) to the ones used in the AoF source code
  • Memory chip pinouts
  • Finish PRO chipset pinouts !
  • M1 and S1 ROM speeds
  • CD I/O ERROR 0001 0002 0003 ?
  • CRC32 of all known ROMs/ISOs from MAME's neogeo.inc
  • Add more jumper configs
  • Memory card stuff (format, banks...)
  • neo-mga on mv1a + PALs info
  • Chip functions for each kind of board (even discrete logic)
  • NEOGEO chip sizes, like pitch, span and body (useful for finding drop-in replacements like CPLD or Castellated pcb boards with replacement chips)

Trivia

  • Add links to TCRF pages for the debug DIPs of each game
  • CMC fix bankswitching: how/when is vram bank info sent to the cartridge?
  • Recent security chips info (SMA, PVC...)
  • Neo cd chip pinouts (not very useful)
  • Are the two missing FM channels from the YM2610 actually off the die or just disabled?

Analysis / mysteries

  • Why does the L0 ROM need an output buffer ?
  • Loading time graphs for all CD games, is MESS reliable enough ? (no)
  • Details on CD registers
  • CDDA playback (needs more research in CD system rom)
  • Dump LC98000 version Neo CD system rom
  • LC8953/98000 microcode (note: Sanyo tech support has nothing left except publicly available brief sheet)

Verify

  • Check Clock distribution diagram, especially on cart edge
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