Difference between revisions of "Sega Mega-CD/Boot ROM"

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(Turns out that one was just the standard revision with a bad HINT vector)
(Turns out that one was just the standard revision with a bad HINT vector)
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{{rom|MCD|sha1=|md5=|crc32=e7e3afe2|size=|date=|source=[[Sega CD]] (NA) (1.00)|comments=|quality=|file=MCD BIOS US v1.00.7z}}
 
{{rom|MCD|sha1=|md5=|crc32=e7e3afe2|size=|date=|source=[[Sega CD]] (NA) (1.00)|comments=|quality=|file=MCD BIOS US v1.00.7z}}
 
{{rom|MCD|sha1=|md5=|crc32=c6d10268|size=131072|date=1992-10-11|source=[[Sega CD]] (NA) (1.10 Rev B)|comments=MK-1690 MPR-15045B-T|quality=|file=MCD BIOS US v1.10B 921011.7z}}
 
{{rom|MCD|sha1=|md5=|crc32=c6d10268|size=131072|date=1992-10-11|source=[[Sega CD]] (NA) (1.10 Rev B)|comments=MK-1690 MPR-15045B-T|quality=|file=MCD BIOS US v1.10B 921011.7z}}
 +
{{rom|MCD|sha1=c905b89c85b44fb0048ad1dc1da6a60a7f50a346|md5=742b4b7ae51aa11551bdbf02e94125ce|crc32=58c94b97|size=131072|date=1992-10-19|source=[[Sega CD]] (NA) (1.10 Rev B) (Prototype)|comments=Found in Sega Dev Machine Archive disk|quality=|file=MCD BIOS US v1.10B 921019.7z}}
 
{{rom|MCD|sha1=|md5=|crc32=529ac15a|size=|date=1992-10-27|source=[[Sega Mega-CD]] (EU) (1.00)|comments=MK-1690-18|quality=|file=MCD BIOS EU v1.00 921027.7z}}
 
{{rom|MCD|sha1=|md5=|crc32=529ac15a|size=|date=1992-10-27|source=[[Sega Mega-CD]] (EU) (1.00)|comments=MK-1690-18|quality=|file=MCD BIOS EU v1.00 921027.7z}}
  

Revision as of 14:19, 13 January 2022

Back to: Sega Mega-CD.
The original Japanese Mega-CD boot ROM, version 1.00.

All variants of the Sega Mega-CD come pre-installed with a boot ROM - a menu interface which appears when the console is given power. While a Sega Mega Drive cartridge can boot almost instantaneously, CD-ROMs require verification and loading, which depending on the quality of the disc or drive, can take several seconds. In addition to help drive the CD-ROM, the Mega-CD's boot ROM informs the user that console is in Mega-CD mode, and cruically gives them something more interesting to look at than a blank screen.

Over time, many slightly different boot ROMs were developed by Sega (or its partners), either for localisation purposes, bug fixes or due to changes in hardware. The Wondermega for example has a different style of boot ROM to a standard Mega-CD, while the LaserActive has to accommodate the Mega LD format.

Functions

Most Mega-CD boot ROMs offer the same functionality - principly to run Mega-CD games. Most models can also play music CDs and Japanese models accept CD+G discs. As the Mega-CD also contains on-board memory for save games, the boot ROM allows users to manage data, either by removing save data they no longer need, or by transferring it to a CD BackUp RAM Cart. Later boot ROMs and the LaserActive cull some of these features, possibly as a cost-saving measure or limitations with the hardware.

On the Mega-CD, boot ROMs typically play a music track, while colourful Mega-CD and/or Sega logos dance around, demonstrating the system's rotation and scaling abilities. Boot ROM versions 2.00 and later support use of the Sega Mouse in control port 2, should users what to use that device to navigate the menus.

All of these features (and more) were also made available in the Sega Saturn and Sega Dreamcast, as well as most rival disc-based consoles.

Screenshots

Main screen

  • JP 1.00

  • US 1.00

  • EU 1.00

  • US 1.10

  • JP 2.00

  • US 2.00

  • EU 2.00

  • JP 2.11

  • US 2.21

  • EU 2.21

  • LaserActive 1.02

  • LaserActive 1.04

  • LaserActive 1.05

  • Wondermega 1.00

  • Wondermega 2.00

  • X'Eye 2.00

CD-ROM playback

  • JP 1.00

  • US 1.00

  • EU 1.00

  • JP 2.00-2.11

  • US/EU 2.00

  • Wondermega 1.00

  • Wondermega/X'Eye 2.00

Storage information

  • JP 1.00

  • US/EU 1.00-1.10

  • JP 2.00

Save data menu

  • JP 1.00

  • US/EU 1.00-1.10

  • JP 2.00

ROM dump status

System Hash Size Build Date Source Comments
Sega Mega-CD
 ?
CRC32 8c3e3945
MD5
SHA-1
1993-03-29 LaserActive (NA) (1.02) BIOS header lists version as 0.98 Download.svg (74 kB) (info)
Sega Mega-CD
 ?
CRC32 9f5771d2
MD5
SHA-1
1993-03-29 LaserActive (Japan) (1.02) BIOS header lists version as 0.98 Download.svg (74 kB) (info)
Sega Mega-CD
 ?
CRC32 2ed602d7
MD5
SHA-1
1993-09-22 LaserActive (NA) (1.04) Download.svg (74 kB) (info)
Sega Mega-CD
 ?
CRC32 b24b919d
MD5
SHA-1
1993-08-10 LaserActive (Japan) (1.05) Download.svg (69 kB) (info)
Sega Mega-CD
 ?
CRC32 41af44c4
MD5 e99e30eeffee8201f9eb2c6e219b6fc2
SHA-1 f30d109d1c2f7c9feaf38600c65834261db73d1f
131072 1991-11-14 Sega Mega-CD (Japan) (1.00c) Found on prototype EPROM labeled "1.00c" Download.svg (80 kB) (info)
Sega Mega-CD
 ?
CRC32 3beb1ac2
MD5
SHA-1
Sega Mega-CD (Japan) (1.00 Rev B) HAA-2910 EPR-14088B Download.svg (80 kB) (info)
Sega Mega-CD
 ?
CRC32 f18dde5b
MD5
SHA-1
Sega Mega-CD (Japan) (1.00 Rev C) HAA-2910 EPR-14088C Download.svg (80 kB) (info)
Sega Mega-CD
 ?
CRC32 1d9756a3
MD5
SHA-1
Sega Mega-CD (Japan) (1.00 Rev D) HAA-2910 EPR-14088D Download.svg (80 kB) (info)
Sega Mega-CD
 ?
CRC32 9d2da8f2
MD5
SHA-1
1991-12-17 Sega Mega-CD (Japan) (1.00 Rev E) HAA-2910 EPR-14088E Download.svg (80 kB) (info)
Sega Mega-CD
 ?
CRC32 79f85384
MD5
SHA-1
Sega Mega-CD (Japan) (1.00 Rev H) HAA-2910 EPR-14088H, MPR-14088H-T Download.svg (80 kB) (info)
Sega Mega-CD
 ?
CRC32 4be18ff6
MD5
SHA-1
1992-05-01 Sega Mega-CD (Japan) (1.11) Dumped from Japanese model 2 sample/prototype Download.svg (81 kB) (info)
Sega Mega-CD
 ?
CRC32 550f30bb
MD5
SHA-1
1991-12-28 Sega Mega-CD (Asia) (1.00 Rev H) Download.svg (80 kB) (info)
Sega Mega-CD
 ?
CRC32 e7e3afe2
MD5
SHA-1
Sega CD (NA) (1.00) Download.svg (85 kB) (info)
Sega Mega-CD
 ?
CRC32 c6d10268
MD5
SHA-1
131072 1992-10-11 Sega CD (NA) (1.10 Rev B) MK-1690 MPR-15045B-T Download.svg (85 kB) (info)
Sega Mega-CD
 ?
CRC32 58c94b97
MD5 742b4b7ae51aa11551bdbf02e94125ce
SHA-1 c905b89c85b44fb0048ad1dc1da6a60a7f50a346
131072 1992-10-19 Sega CD (NA) (1.10 Rev B) (Prototype) Found in Sega Dev Machine Archive disk Download.svg (85 kB) (info)
Sega Mega-CD
 ?
CRC32 529ac15a
MD5
SHA-1
1992-10-27 Sega Mega-CD (EU) (1.00) MK-1690-18 Download.svg (81 kB) (info)
Sega Mega-CD
 ?
CRC32 dd6cc972
MD5
SHA-1
1992-12-22 Sega Mega-CD 2 (Funai Model) (Japan) (2.00) HAA-2912 MPR-15398-T Download.svg (79 kB) (info)
Sega Mega-CD
 ?
CRC32 8af65f58
MD5
SHA-1
1993-03-14 Sega CD 2 (Funai Model) (NA) (2.00) MK4102 MPR-15511-T Download.svg (85 kB) (info)
Sega Mega-CD
 ?
CRC32 9f6f6276
MD5
SHA-1
1993-06-01 Sega CD 2 (Funai Model) (NA) (2.00 Rev A) MK4102 MPR-15511A-T Download.svg (85 kB) (info)
Sega Mega-CD
 ?
CRC32 0507b590
MD5
SHA-1
1993-03-30 Sega Mega-CD II (Funai Model) (EU) (2.00) MK4102-50 MPR-15512-T Download.svg (83 kB) (info)
Sega Mega-CD
 ?
CRC32 4d5cb8da
MD5
SHA-1
1993-06-01 Sega Mega-CD II (Funai Model) (EU) (2.00 Rev A) MK4102-50 MPR-15512A-T Download.svg (83 kB) (info)
Sega Mega-CD
 ?
CRC32 2e49d72c
MD5
SHA-1
1993-06-21 Sega CD 2 (Sony Model) (NA) (2.11) MK-4102A MPR-15764-T Download.svg (86 kB) (info)
Sega Mega-CD
 ?
CRC32 c1aa217f
MD5
SHA-1
1993-06-21 Sega Mega-CD II (Sony Model) (EU) (2.11) MK-4102A-50 MPR-15811-T Download.svg (84 kB) (info)
Sega Mega-CD
 ?
CRC32 d48c44b5
MD5
SHA-1
1993-09-07 Sega CDX (NA) (2.21x) MK-4121 MPR-16139-T Download.svg (86 kB) (info)
Sega Mega-CD
 ?
CRC32 aacb851e
MD5
SHA-1
1993-09-16 Sega Multi-Mega (EU) (2.21x) MK-4121-50 OPR-16140 Download.svg (84 kB) (info)
Sega Mega-CD
 ?
CRC32 d21fe71d
MD5
SHA-1
1992-02-06 Sega Wondermega (Japan) (1.00) HWM-5010 G301 Download.svg (79 kB) (info)
Sega Mega-CD
 ?
CRC32 2b19972f
MD5
SHA-1
Victor Wondermega M2 (Japan) (2.00) RG-M2 G303[n 1] Download.svg (81 kB) (info)
Sega Mega-CD
 ?
CRC32 290f8e33
MD5
SHA-1
1993-12-27 JVC X'Eye (NA) (2.00) RG-M10BU G304 Download.svg (80 kB) (info)
Sega Mega-CD
 ?
CRC32 12154531
MD5
SHA-1
Aiwa CSD-G1M (JP) (2.11) MPR-15768-T Download.svg (80 kB) (info)

Notes

  1. ↑ [The ZIP file contains two dumps, a "good" dump and a "bad" dump. The "bad" dump has an incorrect HINT vector, but is otherwise identical to the "good" dump. The CRC32 listed here is for the "good" dump. The ZIP file contains two dumps, a "good" dump and a "bad" dump. The "bad" dump has an incorrect HINT vector, but is otherwise identical to the "good" dump. The CRC32 listed here is for the "good" dump.]

References


Sega Mega-CD
Topics Technical specifications | History | Magazine articles | Promotional material
Hardware Mega CD (Asia | North America | Western Europe | Eastern Europe | South America | Australasia | Africa)
Sega Multi-Mega (Asia | North America | Europe | South America | Australasia)
Wondermega | LaserActive | CSD-G1M
Misc. hardware CD BackUp RAM Cart | Mega-CD Karaoke | Pro CDX
Development tools SNASM Mega-CD | PsyQ Mega-CD SDK | PSY-Q CD Emulation System (Mega-CD)
Unreleased hardware Game Genie
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