Dreamcast TEST GD-ROM "GD Drive repear program ver 0.1

Discussion in 'Sega Dreamcast Development and Research' started by Laurent, Nov 21, 2017.

  1. Laurent

    Laurent Spirited Member

    Joined:
    Oct 19, 2015
    Messages:
    165
    Likes Received:
    524
    I found some interesting disc

    20171121_101748.jpg

    I presume its To repear build . I don t really know

    20171121_090055.jpg 20171121_100530.jpg
    20171121_093433.jpg
    20171121_101315.jpg 20171121_090129.jpg
     
  2. -=FamilyGuy=-

    -=FamilyGuy=- Site Supporter 2049

    Joined:
    Mar 3, 2007
    Messages:
    3,097
    Likes Received:
    1,045
    Interesting find!

    It looks like a diagnostic disc used for official repairs.
     
    Anthony817, DeChief and Traace like this.
  3. Laurent

    Laurent Spirited Member

    Joined:
    Oct 19, 2015
    Messages:
    165
    Likes Received:
    524
    Its look like the same of the dreamcast C1/C2 checker ( console) ...
     
  4. HI_Ricky

    HI_Ricky Intrepid Member

    Joined:
    Jun 7, 2007
    Messages:
    669
    Likes Received:
    211
    nice stuff :)
     
  5. Laurent

    Laurent Spirited Member

    Joined:
    Oct 19, 2015
    Messages:
    165
    Likes Received:
    524
    I have 2 GD driver repear program v 0.1 and 2 dc checker for repear ( silver ) To trade....

    Its maybe To check a master before his duplication...
     
  6. Mrneo240

    Mrneo240 Enthusiastic Member

    Joined:
    Sep 15, 2017
    Messages:
    519
    Likes Received:
    624
    what kind of trade are you thinking?
     
  7. darcagn

    darcagn Site Supporter 2013, Site Supporter 2014

    Joined:
    May 13, 2007
    Messages:
    557
    Likes Received:
    291
    I have purchased 1 of each, so stock is running out. ;)

    I will do a dump and MIL-CD conversion for both when I receive, even though I know at least the DC checker has been released before.
     
    MetalliC and pool7 like this.
  8. -=FamilyGuy=-

    -=FamilyGuy=- Site Supporter 2049

    Joined:
    Mar 3, 2007
    Messages:
    3,097
    Likes Received:
    1,045
    I had the loop checker GDI at one point and I may have made a mil-cd, but it's lost now so I'm very interested.
     
  9. darcagn

    darcagn Site Supporter 2013, Site Supporter 2014

    Joined:
    May 13, 2007
    Messages:
    557
    Likes Received:
    291
    Looked through my files and I do still have the dump of the DC checker, along with the MIL-CD that atreyu187 made.

    Regardless, I'll do another dump (if it's the same as the existing dump we'll get a match for TOSEC, if it's different then perhaps we'll discover a new software version). And I've never seen this GD Drive Repair program before, so it'll be interesting to play with it and dump it.
     
    RaZiel likes this.
  10. darcagn

    darcagn Site Supporter 2013, Site Supporter 2014

    Joined:
    May 13, 2007
    Messages:
    557
    Likes Received:
    291
    This appears to be correct.

    Software on the disc shows "Ver0.2" in the upper right corner when running the test (see screenshots above).

    The C1/C2 Checker console has the system wired up with a custom BIOS and a serial port. The custom BIOS boots directly to this checker program. The checker program on the console in the example is "Ver0.3" however.

    Here are pictures and a screenshot from Wombat.
    Ba0aHxD.jpg ckL4Gcnl.jpg iCN1PSI.jpg SlvLbRb.jpg



    From what I can gather, this disc was intended to test GD drives during the repair process.
    The C1/C2 checker was intended to test discs during the manufacturing process.
    Both of them use the same software code to test in these different use cases?
     
  11. PrOfUnD Darkness

    PrOfUnD Darkness Familiar Face

    Joined:
    Mar 13, 2004
    Messages:
    1,122
    Likes Received:
    48
    So a custom bios for C1/C2 checker, was it dumped?
     
  12. Laurent

    Laurent Spirited Member

    Joined:
    Oct 19, 2015
    Messages:
    165
    Likes Received:
    524
    its whats i understand:

    You burn the build from your dev kit on a GD-R . Thats your Master

    You use this disk to be sure his correct , his conform

    You send after your master to the editor or publisher.

    The publisher use the GD-R on a duplicator kit to....

    process of compl├Ęte week checking is maybe 8 - 12 hours. I stopped after 4 hours.

    random seek checking of a beta doesn t boot

    20171127_204315.jpg
    track checking
    20171127_205721.jpg
    other
    20171127_205852.jpg
    20171127_210021.jpg
     
  13. darcagn

    darcagn Site Supporter 2013, Site Supporter 2014

    Joined:
    May 13, 2007
    Messages:
    557
    Likes Received:
    291
  14. MetalliC

    MetalliC Spirited Member

    Joined:
    Apr 23, 2014
    Messages:
    180
    Likes Received:
    133
    it seems was like that in early times, later it was changed to submit product as both GD-Rs and master disk(s) image(s) in CDCraft CIM format on tape drive.
    from SDK SOEGDMastering.ppt:
    dcsub.png dcsub1.png
     
    PrOfUnD Darkness and darcagn like this.
  15. PrOfUnD Darkness

    PrOfUnD Darkness Familiar Face

    Joined:
    Mar 13, 2004
    Messages:
    1,122
    Likes Received:
    48
  16. -=FamilyGuy=-

    -=FamilyGuy=- Site Supporter 2049

    Joined:
    Mar 3, 2007
    Messages:
    3,097
    Likes Received:
    1,045
    It's a special hardware revision.
     
  17. MetalliC

    MetalliC Spirited Member

    Joined:
    Apr 23, 2014
    Messages:
    180
    Likes Received:
    133
    all ? there is only 2 parts of security: 1) bios rom checksum protection (calculated by HOLLY chipset); 2) 2x GD-ROM commands, which supposedly check disk security ring wobbling.
    1st part is not a problem, since Sega knows sum algorithm (but we still don't :( ).
    2nd part - I'd guess they simply omit that 0x70/0x71 sec check commands, same as do Dev.Box bios roms.
     
  18. PrOfUnD Darkness

    PrOfUnD Darkness Familiar Face

    Joined:
    Mar 13, 2004
    Messages:
    1,122
    Likes Received:
    48
    SEGA probably changed the HOLLY chipset to disable the first check, like FG said. Interesting nonetheless.
     
  19. -=FamilyGuy=-

    -=FamilyGuy=- Site Supporter 2049

    Joined:
    Mar 3, 2007
    Messages:
    3,097
    Likes Received:
    1,045
    Also, they have the blueprints/sourcecode to everything. They can sign their own bios however they like.
     
  20. MetalliC

    MetalliC Spirited Member

    Joined:
    Apr 23, 2014
    Messages:
    180
    Likes Received:
    133
    manufacture special chipset version for some C1/C2 checker unit ? it doesn't look sane.
    also I don't think Sega itself designed or manufactured any of chips used in Dreamcast, as for HOLLY chipset, ie heart of Dreamcast - it is mostly Videologic made (possible DMA, G1/G2/Maple buses, etc parts was by NEC, but I doubt in this), so its more like UK developed, not Japanese at all :rofl:

    right, I'd bet is was like that.
     
    Last edited: Nov 30, 2017

Share This Page