diff options
author | Angelo Salese <angelosa@users.noreply.github.com> | 2013-08-26 13:47:01 +0000 |
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committer | Angelo Salese <angelosa@users.noreply.github.com> | 2013-08-26 13:47:01 +0000 |
commit | 544546210b352b3818d1f477950b0a8f2b44d83a (patch) | |
tree | 0ce15fe091240f4239558367efae55b029bfaf92 /src/mess/drivers/dccons.c | |
parent | 05dad0b0e3820f2d7652a3dc30ab4648f35bef35 (diff) |
(MESS) Fix GD-Rom booting in DC US and PAL [PsyMan]
Diffstat (limited to 'src/mess/drivers/dccons.c')
-rw-r--r-- | src/mess/drivers/dccons.c | 50 |
1 files changed, 49 insertions, 1 deletions
diff --git a/src/mess/drivers/dccons.c b/src/mess/drivers/dccons.c index 1a6f527db24..79f08e17519 100644 --- a/src/mess/drivers/dccons.c +++ b/src/mess/drivers/dccons.c @@ -400,6 +400,54 @@ static MACHINE_CONFIG_START( dc, dc_cons_state ) MCFG_DEVICE_ADD("cdrom", GDROM, 0) MACHINE_CONFIG_END +/* +PsyMan notes: + +Here's a basic report on the Dreamcast boot files used in MAME (BIOS+Flash pairs): + +----- + +"dc101d_us.bin", 0x000000, 0x200000, CRC(89f2b1a1) SHA1(8951d1bb219ab2ff8583033d2119c899cc81f18c) ) // BIOS +This is a proper European and USA BIOS. It's even possible that it was used at a later point for Japanese systems. +It only has minor differences compared to BIOS 1.01c. + + +"dcus_ntsc.bin", 0x000000, 0x020000, BAD_DUMP CRC(c611b498) SHA1(94d44d7f9529ec1642ba3771ed3c5f756d5bc872) ) // Flash +Checking at 0x0001A000 and the mirrored data at 0x0001A0A0 gives away that this is hacked from a PAL/European flash file. +The broadcast (0x0001A004) is also set at 50Hz which is a PAL standard. + + +"dc101d_eu.bin", 0x000000, 0x200000, CRC(a2564fad) SHA1(edc5d3d70a93c935703d26119b37731fd317d2bf),ROM_BIOS(1)) // BIOS +This BIOS has Chinese language added. So either this is a bad BIOS or Dreamcast was actually officially released there. + + +"dc101c_eu.bin", 0x000000, 0x200000, CRC(2f551bc5) SHA1(1ede8d5be49116a4c6f3fe0961175469537a0434),ROM_BIOS(2)) // BIOS +This seems to be a proper European and USA BIOS. It's even possible that it was used at a later point for Japanese systems. +It only has minor differences compared to BIOS 1.01d. + + + +"dceu_pal.bin", 0x000000, 0x020000, BAD_DUMP CRC(b7e5aeeb) SHA1(11e02433e13b793ec7ffe0ae2356750bb8a575b4) ) // Flash +This appears to be a valid PAL/European flash. It's unknown if the data at 0x0001A0A0 (from 0x0001A000) should be mirrored there. +Maybe a game does this mirroring or maybe it's there by default. It's certain that some games wrote to this flash though. + + +"dc1004jp.bin", 0x000000, 0x200000, CRC(5454841f) SHA1(1ea132c0fbbf07ef76789eadc07908045c089bd6) ) // BIOS +This seems to be a proper Japanese BIOS. This BIOS was used at least by early Japanese Dreamcast models. +Code-wise, it has major differences compared to later BIOS versions. + + +"dcjp_ntsc.bin", 0x000000, 0x020000, CRC(5F92BF76) SHA1(BE78B834F512AB2CF3D67B96E377C9F3093FF82A) ) // Flash +Checking at 0x0001A000 and the mirrored data at 0x0001A0A0 gives away that this is hacked from a PAL/European flash file. +The broadcast (0x0001A004) is also set at 50Hz which is a PAL standard. + +----- + + +From all the aforementioned files the only personally verified one is "dc101d_us.bin", CRC(89f2b1a1). +The resulting file was dumped twice, once from an NTSC/USA system and once from a PAL/EUR system. Both files had a side by side byte match. +*/ + ROM_START(dc) ROM_REGION(0x200000, "maincpu", 0) ROM_LOAD( "dc101d_us.bin", 0x000000, 0x200000, CRC(89f2b1a1) SHA1(8951d1bb219ab2ff8583033d2119c899cc81f18c) ) // BIOS @@ -425,7 +473,7 @@ ROM_START( dcjp ) ROM_REGION(0x020000, "dcflash", 0) /* ROM_LOAD( "dcjp_ntsc.bad", 0x000000, 0x020000, BAD_DUMP CRC(307a7035) SHA1(1411423a9d071340ea52c56e19c1aafc4e1309ee) ) // Hacked Flash */ - ROM_LOAD( "dcjp_ntsc.bin", 0x000000, 0x020000, CRC(5F92BF76) SHA1(BE78B834F512AB2CF3D67B96E377C9F3093FF82A) ) // Flash + ROM_LOAD( "dcjp_ntsc.bin", 0x000000, 0x020000, BAD_DUMP CRC(5F92BF76) SHA1(BE78B834F512AB2CF3D67B96E377C9F3093FF82A) ) // Flash ROM_END ROM_START( dcdev ) |