Dreamcast region free BIOS

Discussion in 'Sega Discussion' started by FireAza, Jun 28, 2012.

  1. AlmostOriginal

    AlmostOriginal Spirited Member

    Joined:
    Aug 16, 2011
    Messages:
    122
    Likes Received:
    0
    omp: Thank you for your help. I am pretty sure my soldering is good. I have checked them all and they are good. (Maybe i have to check it again) I am almost in the same boat as beharius. 1 works the other one doesnt.

    Broken
    [​IMG]

    Working
    [​IMG]

    The reason Leg 44 of the chip is not wired to leg 7 of IC502 is because i use this:
    http://www.mmmonkey.co.uk/sega-dreamcast-region-free-bios/#ic502

    Side note this was much easier than that nightmare saturn bios.
     
    Last edited: Mar 24, 2013
  2. beharius

    beharius Resolute Member

    Joined:
    Sep 13, 2011
    Messages:
    923
    Likes Received:
    101
    Leg 44 (WE) can also be connected to the pin B14 of the GDROM connector(CN503)...
     
  3. Bad_Ad84

    Bad_Ad84 The Tick

    Joined:
    May 26, 2011
    Messages:
    8,548
    Likes Received:
    1,231
    WE can also be connected to VCC (pin 23) - it just means you cant write to the chip
     
  4. APE

    APE Site Supporter 2015

    Joined:
    Dec 5, 2005
    Messages:
    6,416
    Likes Received:
    138
    The only incompatibility I've come across after modding 50+ DCs is a DC where the GD-ROM won't properly read discs anymore and I'm pretty sure it's a GD-ROM problem and not a BIOS issue.
     
  5. Lum

    Lum Officer at Arms

    Joined:
    Sep 30, 2010
    Messages:
    3,231
    Likes Received:
    39
    Oh no, please don't let me be the unlucky "winner" if I ever have to replace my DC. Already bad enough that similar happened when modding GC.
     
  6. APE

    APE Site Supporter 2015

    Joined:
    Dec 5, 2005
    Messages:
    6,416
    Likes Received:
    138
    I doubt it, I think the GD-ROM on this thing isn't seated 100% but I've been too lazy to bother trying to reseat it.
     
  7. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
    Pad 18 lifted off my mother board while removing the original bios , there's no trace . Can anyone tell me where pad 18 connects to alternatively ?
     
  8. Bad_Ad84

    Bad_Ad84 The Tick

    Joined:
    May 26, 2011
    Messages:
    8,548
    Likes Received:
    1,231
    Pin 18 isn't used.

    For users of the future, pins 16,18,20,22,25,27 and 29 aren't used, as the chip is used in 8 bit mode, not 16 bit.
     
    Last edited: Nov 1, 2016
  9. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
    Ah ok thanks so much . I went ahead and installed the new bios chip but I only get the original saga swirl logo screen but with out animation :/ it just pops on screen and does nothing else :(

    I'll post a pic when I figure out how to actually post a pic on here .
     
  10. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
    This is before installation . I'll take a pic of the installed chip when I get off work and post it .
     

    Attached Files:

  11. Bad_Ad84

    Bad_Ad84 The Tick

    Joined:
    May 26, 2011
    Messages:
    8,548
    Likes Received:
    1,231
    You need the gdrom installed.

    If you get the logo, the chip install is fine.
     
  12. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
    The gdrom is installed , spins up and reads . But the screen just pops to the orange swirl and stays there .
    And the vmu beeps but no display ever appears .
     
  13. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
    Pics
     

    Attached Files:

  14. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
    And instead of the original logo screen shouldn't it be the new/development screen ?
     
  15. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
    Ok so it stays on this screen for about 3 minutes and then goes to the the menu screen where it says please wait while checking disc but then does nothing . Just stays at that screen . Wtf is going on !
     

    Attached Files:

  16. l_oliveira

    l_oliveira Officer at Arms

    Joined:
    Nov 24, 2007
    Messages:
    3,879
    Likes Received:
    245
    Likely you broke a trace which goes to the GD ROM connector and now the console cannot communicate with the GD ROM unit. The traces come from the Holly chip (GPU) pass through the flash rom (memory with settings) then through the BIOS and finally end on the GD-ROM drive connector. It's possible that you tore the trace in a way it's severed between the rom and the GD connection, so it still can read the rom but fails to communicate with the GD properly.
     
  17. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
  18. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
    Na the direction of mmmonkey's are totally wrong in every way .

    pin 23 "not lifted" and pin 44 "lifted" are wired together and pin 1 "lifted" is wired to pin 7 of the IC502 chip.

    As directed by bad_ad84 to another person in that other thread . I guess he just forgot to mention it .
     
  19. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
    Wrong way
     

    Attached Files:

  20. Greg young

    Greg young Member

    Joined:
    Nov 1, 2016
    Messages:
    18
    Likes Received:
    0
    Correct way
     

    Attached Files:

Share This Page