Three Bios-Chips in one AES

Mystery

Mystery

Sakura's Bank Manager
Joined
Jul 19, 2001
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737
Right now I've got an US and JP bios I can switch between.
Within the next days I'll hopefully recieve a debug bios.
Now I want to put this as a third bios on top of the other two.
I think I need a 3way switch and some other things. Since I've got no experience in adding another Bios Chip (especially a third one) I'd be glad if someone could provide some detailed information about required parts and an exact description of the single steps to add this third bios to my NeoGeo :)
 
A

Amano Jacu

Charles Barkley
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Sep 11, 2001
Posts
8,594
Wow, that looks kinda complicated. I guess you already know it but try this link <a href="http://www.hardmvs.com" target="_blank">www.hardmvs.com</a>
 
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Arakon

Robert Garcia's Butler
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takes more than a three way switch.
I recommend you simply desolder the top bios and add the debug one instead. besides, it's gonna get mighty full in there with yet another chip on top.
 
Mystery

Mystery

Sakura's Bank Manager
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I know that it's not going to be easy.
If I wanted to replace the JP Bios with the Debug Bios I wouldn't have asked how to do it :)

Nobody has an idea how to make this work? :(
 
A

Arakon

Robert Garcia's Butler
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I can just tell you this much.. you need to put +5V on pin 20 of BOTH the bios's you DON'T use, and connect the pin of the bios you DO use to the connection point on the PCB.
I guess the only decent way to do this would be with 2 flipswitches OR a 3 position turnswitch. although using a hexinverter might work (with a single 3 position flipswitch), but you'd have to figure the pinout out yourself.
 
J

JMKurtz

Tech Support Moderator,
20 Year Member
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Aug 12, 2000
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Yea, I can tell you how to do it and it's going to require an additional switch. It's not complicated.

Drop me a line at jmkurtz@columbus.rr.com and I'll write up some instructions for you.

Jeff
 
C

Clear Paper

,
Joined
Aug 30, 2001
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Just a note, if your stack is southeast of the cartridge slot, it may come in contact with the cart when you insert it. May have to shift them right a bit by bending the pins.
 
Mystery

Mystery

Sakura's Bank Manager
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Thanks for all the tips folks...I'll tell you later if I succeeded! :)

Jeff, you've got mail!
 
playboycougar

playboycougar

Reese. ,
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Dec 8, 2001
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Originally posted by JMKurtz:
<strong>Yea, I can tell you how to do it and it's going to require an additional switch. It's not complicated.

Drop me a line at jmkurtz@columbus.rr.com and I'll write up some instructions for you.

Jeff</strong><hr></blockquote>
May I just note that Jeff is the man... :)
Click to expand...
 
Mystery

Mystery

Sakura's Bank Manager
Joined
Jul 19, 2001
Posts
737
Ok...thanks, Jeff for the detailed description!

I gathered all the necessary parts to begin assembling the thing but I encountered a (serious?) problem.

Both pin20 are cut and bent off the board, wired to the switch and to resistors. I don't know how to describe it, but I think it's not assembled after the standard method.

Jeff: I dropped you a mail with a picture and a detailed description of the problem. Hopefully you can help me solve this thing.
 
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