ROM Size 0x80000000? Or 0?
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ROM Size 0x80000000? Or 0?
In the Soldam_(Jaleco_Mega_System_1) pack, the following data blocks sequence can be found: 67 66 8b 08 00 00 80 00 00 04 00 00 00 00 00. What am I to make of the data size of 0x80000008? 8 of that is the subheader for the ROM write, leaving 0x80000000. This game appears to use 2 Oki M6295s, so I might hypothesize that the high bit means it's the ROM for the second chip, but that leaves me with a ROM data size of 0, which is clearly incorrect as data follows the ROM write subheader.
- ValleyBell Offline
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Data size 0x80000008 indeed means "size 0x08, 2nd chip". (I guess that I also forget to document this.)
The size includes the ROM header, which is 8 bytes and followed by the actual data that is to be loaded into the ROM space.
In this case, the data block has: data size 0x08, ROM size 0x40000, start offset 0x00, [no actual payload].
This effectively means that it will just allocate the 256 KB of ROM space for the second OKI chip and not fill it with any data.
The size includes the ROM header, which is 8 bytes and followed by the actual data that is to be loaded into the ROM space.
In this case, the data block has: data size 0x08, ROM size 0x40000, start offset 0x00, [no actual payload].
This effectively means that it will just allocate the 256 KB of ROM space for the second OKI chip and not fill it with any data.