Thanks for the reply.
From the driver:
static ADDRESS_MAP_START( gunsmoke_map, ADDRESS_SPACE_PROGRAM, 8 )
AM_RANGE(0x0000, 0x7fff) AM_ROM
AM_RANGE(0x8000, 0xbfff) AM_ROMBANK(1)
AM_RANGE(0xc804, 0xc804) AM_WRITE(gunsmoke_c804_w) // ROM bank switch, screen flip
and
ROM_START( gunsmoku )
ROM_REGION( 0x20000, "main", 0 )
ROM_LOAD( "9n_gs03.bin", 0x00000, 0x8000, CRC(592f211b) SHA1(8de44b3cafa3d2ce9aba515cf3ec4bac0bcdeb5b) ) /* Code 0000-7fff */
ROM_LOAD( "10n_gs04.bin", 0x10000, 0x8000, CRC(8d4b423f) SHA1(149274c2ed1526ca1f419fdf8a24059ff138f7f2) ) /* Paged code */
ROM_LOAD( "12n_gs05.bin", 0x18000, 0x8000, CRC(2b5667fb) SHA1(5b689bca1e76d803b4cae22feaa7744fa528e93f) ) /* Paged code */
ROM_LOAD 9n_gs03.bin is straight forward.
Why does ROM_LOAD gs04 and gs05 appear to be loaded 'backwards' into memory? i.e. 0x10000, 0x8000 and 0x18000, 0x8000.
Please help me understand whats going on here. From what I understand about ROM banking is that banking is fooling the CPU into executing two separate programs as a single program. Is this what is happening here?
How can the code be disassembled correctly?
Thanks for your time.
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Re: Help with Code disassembly
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