シルヴァ・サーガ / Silva Saga PCB scan

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シルヴァ・サーガ / Silva Saga PCB scan
by on (#126036)
PCB class: Nintendo HVC-TKROM-03
U1 PRG: KKS-SR-0 PRG, ROM 0x40000 byte, CRC32: 0xfe94066d
U2 CHR: KKS-SR-0 CHR, ROM 0x40000 byte, CRC32: 0x45c35b65

high resolution and other sides scan
http://www1.axfc.net/u/3179298.zip

Many emulators display illegal save datas at first time. This ROM images is marked as 'Baddump' in some databases. This is wrong. Many emulators don't emulate 'uninitialized' SRAM data.

- .sav file がない場合、エミュレータは $6000-$7fff を 0 で埋める。
- Silva Saga の Program は $6000-$7fff が 0 で埋まっていると「正常」なデータと認識するので、セーブデータの初期化をしない
- 「正常」と認識されたデータは実際には「不正」なのでゲームが進行しない

対策: non volatile data (SRAM) の初期値を 0 で埋めてはいけない
Re: シルヴァ・サーガ / Silva Saga PCB scan
by on (#128310)
it took a lot of time, but I managed to implement per-game SRAM support when loading from software lists
this finally allows Silva saga to be playable in MESS (and I will soon use it for a couple of SNES games which need it as well)

thanks a lot for the info