Replacement options for dead Chihiro board

Discussion in 'Chihiro Development' started by leetwolf, May 15, 2018.

  1. leetwolf

    leetwolf Peppy Member

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    Hello guys,

    My Chihiro board recently died, I tried to fix it but cannot identify the fault. I was wondering what my options are for replacing it? I was ideally hoping to solder a header onto a retail board and solder some more RAM and maybe get things running? It was a Type 1

    Is it possible to run segaboot.xbe on a modded system and get things going? I'd be running House of the Dead 3 since thats the only game I have. I have the GD-ROM, which I assume will be useless if I went this route, or can I somehow run the GD-ROM?

    Really looking for some pro help here.
     
    Last edited: May 15, 2018
  2. Syclopse

    Syclopse .

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    Speak with @nonosto as he's always working with these units.
     
  3. TriMesh

    TriMesh Site Supporter 2013-2017

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    The board in the Chihiro is basically the same as a debug kit except for the flash contents. Specifically, it has 128MB of RAM and a MCP X2 (the one that boots from flash rather than the internal ROM) on it. Reflashing the TSOP on a Chihiro mother board with the boot ROM from a debug kit turns it into a debug kit, which can then be updated using the standard MS restore discs.

    I assume you can go the other way, too, although I don't know if the Chihiro has specific EEPROM contents.

    The upshot of this is that a retail board won't boot with a Chihiro boot ROM even if you upgrade the RAM because the boot code is wrong.
     
  4. leetwolf

    leetwolf Peppy Member

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    I guess what I'm trying to find out is, why I couldn't manually run the segaboot file? Wouldn't the LPC still work?
    Can't it still load the game via the GD-ROM? Or is it safe to assume the LPC is not going to work. I was thinking I could use PBL and load the debug bios then just run the game?

    Am I missing something?
     
    Last edited: May 15, 2018
  5. obcd

    obcd Rising Member

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    The chihiro dimm is seen as ide device 0 It's split up into several partitions. The mbrom partition contains segaboot.xbe. The chihiro bios uses different xor keys in the segaboot.xbe header section. For that reason, segaboot.xbe will refuse to run on a normal retail or debug bios.

    I also wonder how you will reflash the tsop of a chihiro board? You would need a way to run homebrew or linux on a chihiro board.

    The 3 most common failures of chihiro boards are:
    1. An overheating gpu due to a non working gpu fan. It's easy to spot as the fan isn't running and the pcb is severe decolored brownish at the back under the gpu.
    2. The capacitors surrounding the cpu have dryed out. Sometimes you can see it as their top is bulged. Sometimes it's hard to spot.
    3. The 1 farad goldcap started to leak over the motherboard. The leackage is corrosive and eats up surounding pcb tracks.

    Issue 2 and 3 are sometimes repairable. Issue one would require the replacement of the bga gpu. As the pcb underneath has received 2 much heat as well, pcb tracks might separate from the board during the process.

    So, if you would succeed in creating a BFM compatible chihiro bios, your idea might work. You will need to tsop flash your retail mobo as the stock bios doesn't work with 128MB of ram. Next, you will need to perform a ram update.

    I tried a modchip in a chihiro setup without success. The lpc didn't work with a modchip and the dimm board connected both to it.

    An extra compact flash card or harddrive on the ide interface did work. So you might be able to launch PBL from that device and have it launch another bios.
     
  6. obcd

    obcd Rising Member

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    So the one problem I see is converting a chihiro bios into a "Boot From Memory" one that runs on a retail board.
     
  7. leetwolf

    leetwolf Peppy Member

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    The gold cap did leak, but i cleaned it up. the unit worked like maybe 4 weeks ago? Where are you located? Wanna try fixing it? Otherwise I'm cannibalizing my debug kit to replace this board and i don't want to do that.
     

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