Weird problems with neogeo AES and unibios on a socket (no piggybacking)

BIG BEAR

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Okay you have these three points between pin 19 & 20 of the bios. Check these:
NEO-DO 1 =LSPC2 PIN 5
NEO-DO 2 =LSPC2 PIN 7
NEO-DO 3 =LSPC2 PIN 8
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BIG BEAR

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OK. This point runs under the bios and has atrace close to pin 2.
NEO-C1 96=EO PIN 61
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BIG BEAR

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OK. I forgot to list these to points already mentioned:
These are all connections from the bios to the 68000:
PIN 4 =pIN 55 68000
PIN 5 =PIN 56 68000
PIN 6 =PIN 57 68000
PIN 7 =PIN 58 68000
PIN 8 =PIN 59 68000
PIN 9 =PIN 60 68000
PIN 10 =PIN 61 68000
PIN 12 =PIN 62 68000
PIN 13 =PIN 63 68000
PIN 14 =PIN 64 68000
PIN 15 =PIN 1 68000
PIN 16 =PIN 2 68000
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makinavaja

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OK. I forgot to list these to points already mentioned:
These are all connections from the bios to the 68000:
PIN 4 =pIN 55 68000
PIN 5 =PIN 56 68000
PIN 6 =PIN 57 68000
PIN 7 =PIN 58 68000
PIN 8 =PIN 59 68000
PIN 9 =PIN 60 68000
PIN 10 =PIN 61 68000
PIN 12 =PIN 62 68000
PIN 13 =PIN 63 68000
PIN 14 =PIN 64 68000
PIN 15 =PIN 1 68000
PIN 16 =PIN 2 68000
BB
All tested and all tracks are ok.
 

BIG BEAR

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Ok. I will check back in later on this evening if i find anything else.
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makinavaja

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Just now I've arrived home with two brand new freshly recorded eeproms. One with uni bios 3.3 and other with the diagnosis bios.
Both of them have the same manufacturer and size: all the same.
Unibios 3.3 still have the same results: I can play as long as there are quite enough light and as long I dont place any object near the eeprom.
The other one, just reboots every second, never starts any test seriously :-(
It seems that this eprom is more sensible to everything compared to the other one with the uni bios 3.3 flashed, no matter if both chips are the same!
 

BIG BEAR

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You only started to have problems once you attempted to add a socket so the problem has to be there. I would remove and replace.After you removethe socket make sure none of the connections are bridging. Pins (1,40 &39)(11&30) are already bridged on the board so you don't have to do any bridging.
BB
 
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ack

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With the issue being triggered with light vs no light it seems like something must be up with the eproms themselves. I would try putting the stock bios back in and see what happens. If the issues doesn't happen that further points to the eproms being the cause. Whats their manufacture / model?
 

makinavaja

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You only started to have problems once you attempted to add a socket so the problem has to be there. I would remove and replace.After you removethe socket make sure none of the connections are bridging. Pins (1,40 &39)(11&30) are already bridged on the board so you don't have to do any bridging.
BB

umm, just only thinking about desolder something again from those pins, makes me feel afraid of breaking something again, but with all the info you gave me about all the pins and connections, now that must be much easier!
But, anyway, if there is any undesired bridge there,.. why the console has been working nonstop during one hour withouth problems while my hand was far from the eeprom? :-(

Anyway, again, thank you very much for your help!! I will think about the next move now, and how to do it safely
 
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makinavaja

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With the issue being triggered with light vs no light it seems like something must be up with the eproms themselves. I would try putting the stock bios back in and see what happens. If the issues doesn't happen that further points to the eproms being the cause. Whats their manufacture / model?

The eeproms I puchased are more sensible to light and static electricity compared to the one that razoola shipped me when I purchased the unibios 3.3.

The ones I purchased are "ST", M27C1024- 10f1 5882D 0112L, Those, just switching off the lights from the desktop makes them fail u_u;

Anyway, those eeproms works perfectly on the MVS boards I've got here...
 
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BIG BEAR

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Something is running interference with your bios connection. I would RE-DO and solder all points to the bottom of the board
The fact that the Diagnostic bios does not work is telling.
BB
umm, just only thinking about desolder something again from those pins, makes me feel afraid of breaking something again, but with all the info you gave me about all the pins and connections, now that must be much easier!
But, anyway, if there is any undesired bridge there,.. why the console has been working nonstop during one hour withouth problems while my hand was far from the eeprom? :-(

Anyway, again, thank you very much for your help!! I will think about the next move now, and how to do it safely
 

makinavaja

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botton.jpg

Now, any recomendation? any kind of wire, socket or test to do? Sorry, right now I'm a bit lost in this u_u;
 

BIG BEAR

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You have the list. You are going to have to trace backwards from the component (EO) to the bios.You don't want to connect the wire directly to the component if you don't have to.Use the through holes and that is how you run all your wires from the bottom of the board.If your pinout has no through hole along the trace, you connect from the bios pin and locate a through hole closest to the pin of the component and bring the wire up to attach directly to the pin.
Wire should be kynar 30AWG.
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makinavaja

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Well, before I removed the socket from the board, the connections were made as you said: only one wire was connected directly to the component, as the only track was direct from bios to the chip.
It can be seen how it was before just looking at the video from my first post.

And this is the picture after I improved the bridges thanks to the info you provided me:
after.jpg

And nothing changed. Lets see if with this wire you recommend I can get better results. First I must search and purchase it, and also look for another socket.
 

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BIG BEAR

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When I did a repair I had 3 wires on pin 23 going to 259(3),EO(2) and 68000(31) and two wires on pin 25 going to the EO(4) and 68000(33)
The pin 38 and 40 needs no bridge
Try it.
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Neo Alec

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Big Bear speaks the truth. I have been through this before. I desoldered one with a shitty iron. I should have had my wife do it, and now we have a nice desoldering station.

I had to patch a lot of traces, but eventually got it working. Be mindful of trying bridging/not bridging the final pins, as suggested on the JNX site (you can find the bios pinout on that site too).
 

makinavaja

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hi again
Until next week I wont receive the parcel with the wire and the sockets I ordered u_u;
So my little AES have to wait at the "surgery"...
 
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