Sega Saturn Region Free BIOS

Discussion in 'Sega Saturn Programming and Development' started by Serantes, Jun 12, 2011.

  1. l_oliveira

    l_oliveira Officer at Arms

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    It was VA0.5. DIP. You can't expect me remember the right names/types of everything, considering that I did this at least three or four years ago... :shrug:
     
  2. rosewood

    rosewood Rapidly Rising Member

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    Thanks for testing that out, grips03.
    If you happen to mod a skeleton Saturn too one day then please tell me the results. I guess I'll buy another skeleton then to give that a try.
    Right now I'm glad I could repair it.

    Thanks for the offer, since the chips are confirmed ok it must have been my fault or there is an incompatibility with that special Saturn model.
    I don't know the exact VA revision of the mainboard and don't plan on opening the case again in the near future. But it is possible to get the revision from the serial number. The serial number starts with "B8F", so this must be revision 16 when using the numbering scheme of page 2 of this thread, right?

    Anyways, as soon as I get another Saturn for modding/repair service I'll give it try with the BIOS replacement.
     
  3. Druidic teacher

    Druidic teacher Officer at Arms

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    x
     
    Last edited: Jun 22, 2017
  4. grips03

    grips03 Rising Member

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    I have a heat gun that I use for automotive stuff. This seems to work to remove SMT parts. One question I have is do the parts that get heated up around the area still work? Parts/PCB get pretty hot.
     
  5. APE

    APE Site Supporter 2015

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    A heatgun is a great way to destroy sensitive electronic components. It has no use here.
     
  6. grips03

    grips03 Rising Member

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    APE, that's what I figured. I ordered some of that chip quik and going to try it on some test boards.
     
    Last edited: Aug 1, 2011
  7. DarthCloud

    DarthCloud Fiery Member

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    FYI, I received an original Radiant Silvergun today and it's working perfect with the region free BIOS on my US saturn :D
     
  8. APE

    APE Site Supporter 2015

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    Don't mind the guy in the bushes outside your window in the hockey mask.
     
  9. Patrick

    Patrick Rising Member

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    I just installed the new bios and... it's working :dance:

    I tested several games and they're all booting without a problem, including games with 4MB RAM card (of course with ram card attached). Here's a photo of the new installed bios:
    http://img163.imageshack.us/img163/9066/biosinstalled.jpg

    Unfortunately while removing the original bios, two pads on the pcb where removed too... this is why they're two additional wires.

    Thanks to everyone who made this possible :thumbsup:
     
  10. grips03

    grips03 Rising Member

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    Patrick,
    What method did you use to uninstall the old bios chip?
     
  11. APE

    APE Site Supporter 2015

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    Just got my chips and checked into trying to tie pin 12 to CE to switch between the original and a piggybacked chip, absolutely not.

    The pad doesn't have a top side via to solder to making it difficult to shove a wire under the mask rom. Plus the chips don't line up properly, as a result I can't tell where pin 12 actually exists on the mask rom that I need to lift.

    As a bonus the chip quik I thought I had turned out to be a roll of solder that I lost some time ago. Guess I get to dig through some more boxes.

    EDIT: Me brain no function well before it has preheated to optimal temperatures.

    From what I gather pin 12 is /CE on the Macronix flash chip but pin 12 on the Saturn board isn't the equivalent. Rather its the pad with the white dot silkscreened in front of it with the very obvious grounded pin to its right.

    Unless there is a via or trace somewhere connecting to the equivalent of pin 12 I'm not sure I can rig something up like the Dreamcast. Of course I'm half alseep right now and didn't really look yet so regard this as incoherent rambling.
     
    Last edited: Aug 3, 2011
  12. Patrick

    Patrick Rising Member

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    soldering iron and box cutter blade to lift each pin.
     
  13. Bad_Ad84

    Bad_Ad84 The Tick

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    You could solder to the pad when you have lifted pin 12, there is no reason for a trace to solder to - other than to make it easier.

    Also, you could probably just just drive CE high or low from another source. I dont think it does anything fancy like pulse (not reading datasheet - currently on my phone)


    Should be perfectly possible, tho im not sure as to the reason for it.
     
  14. APE

    APE Site Supporter 2015

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    Right, I was just looking for an easier method than soldering to the pad directly as to eliminate any chance of ruining it or bridging a wire and the mask rom. Part of it was me being a bit impatient with myself at 10am...

    And AFAIK it doesn't need anything other than being driven high or low. I did check out the datasheet to confirm that pin 12 was /CE and what it needed to be wired up properly.
     
  15. APE

    APE Site Supporter 2015

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    Got the first chip installed in a VA8 Saturn and it works great. Bit odd hearing the Japanese Saturn sounds for the first time and a few other minor changes to the GUI I'm unfamiliar with but all is well.

    I ended up using chip quik to pull the old mask rom out, didn't realize there was a bit of glue underneath at first. Ended up straightening the flash ICs legs in the style for the Dreamcast and soldering it down, worked out pretty well. Not sure I'd want to try soldering it in without any modification though.
     
  16. Lum

    Lum Officer at Arms

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    Cool! Good to know it's working that way. It would be a little out of place to have the US bios on this white Saturn, I'd picked up one as I'd mentioned earlier.
     
  17. APE

    APE Site Supporter 2015

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    Personally I'd love to have the boot up animation and sounds match the default region of the console but I'll live.

    On the plus side it does give it a "whoa what is with this" shock value to people who haven't seen it and guarantees that anyone who is worth their spit in Saturn stock knows that this particular Saturn is something special.
     
    Last edited: Aug 15, 2011
  18. fasman

    fasman Enthusiastic Member

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    Just finished fitting the region free bios, what a pain,a few years ago I did 100s of old psone bios replacements(before pic solutions) using the exact same technique and never had a single broken track or pad, did this saturn and it lifted 3 :(, and didn't notice that one of the pads go to two differing Via's (yea my own stupidity).

    [​IMG]

    Also I can confirm a in-correctly fitted bios will give you a black screen...

    Except for that it works a treat on a VA09 Motherboard....

    PS Thanks Bad_Ad84 for the chips.
     
    Last edited: Aug 19, 2011
  19. APE

    APE Site Supporter 2015

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    Fortunately lifting a pad on this BIOS is easy work to fix with all those vias nearby.
     
  20. fasman

    fasman Enthusiastic Member

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    Agreed but you have about a 50% chance that one of the tracks actually lead to a via under the chip, still a easy fix though, just not as neat as I would like it.
     
    Last edited: Aug 20, 2011

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