Socket installation gone bad

RockstarRunner

Wind Jammin' All Night",
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Mar 25, 2004
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I have recently had a socket put in my AES, but it has not gone succesfully, when turned on, garbage appears on screen.

Can anyone post decent instructions on how to test a bios socket installation for problems? Specifically, with a multimeter, what setting to use and what readings to expect.

Note: I know the bios itself is ok.

I hope with the right info I can save my Neo.
 

MKL

Basara's Blade Keeper
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I wrote down the path of each bios trace a while back. I'll see if I can find it...
 

MKL

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This info is taken from NEO-AES3-6 and NEO-AES3-4 revision boards and should be valid for all boards that have the bios to the right of the cart slot. The older board NEO-AES which has the bios above the cart slot is partly different.


1----5V
2----GND
3----68000-12 (54), LSPC2 (21), NEO G0 (50)
4----68000-12 (55), LSPC2 (20), NEO G0 (49)
5----68000-12 (56), LSPC2 (19), NEO G0 (48)
6----68000-12 (57), LSPC2 (18), NEO G0 (47)
7----68000-12 (58), LSPC2 (16), NEO G0 (34)
8----68000-12 (59), LSPC2 (15), NEO G0 (33)
9----68000-12 (60), LSPC2 (14), NEO G0 (32)
10---68000-12 (61), LSPC2 (13), NEO G0 (31)
11---GND
12---68000-12 (62), LSPC2 (10), NEO G0 (18), 43256* (19)
13---68000-12 (63), LSPC2 (9), NEO G0 (17), 43256* (18)
14---68000-12 (64), LSPC2 (8), NEO D0 (3), 43256* (17)
15---68000-12 (1), LSPC2 (7), NEO D0 (2), 43256* (16)
16---68000-12 (2), LSPC2 (5), NEO D0 (1), 43256* (15)
17---68000-12 (3), LSPC2 (4), NEO D0 (64), 43256* (13)
18---68000-12 (4), LSPC2 (3), NEO D0 (63), 43256* (12)
19---68000-12 (5), LSPC2 (2), NEO D0 (62), 43256* (11)
20---NEO E0 (59)
21---68000-12 (29), NEO E0 (64), 43256 (10), HC259 (1)
22---68000-12 (30), NEO E0 (1), 43256 (9), HC259 (2)
23---68000-12 (31), NEO E0 (2), 43256 (8), HC259 (3)
24---68000-12 (32), NEO E0 (3), 43256 (7), HC259 (13)
25---68000-12 (33), NEO E0 (4), 43256 (6)
26---68000-12 (34), NEO E0 (15), 43256 (5)
27---68000-12 (35), NEO E0 (16), 43256 (4)
28---68000-12 (36), NEO E0 (17), 43256 (3)
29---68000-12 (37), NEO E0 (18), 43256 (25)
30---GND
31---68000-12 (38), NEO E0 (19), 43256 (24)
32---68000-12 (39), NEO E0 (20), 43256 (21)
33---68000-12 (40), NEO E0 (21), 43256 (23)
34---68000-12 (41), NEO E0 (31)
35---68000-12 (42), NEO E0 (32)
36---68000-12 (43), NEO E0 (33)
37---68000-12 (44), NEO E0 (34)
38---5V (N.C. on NEO-AES3-4)
39---5V
40---5V

* The 43256 (work RAM) closest to P1 joystick port
 
Last edited:

norton9478

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For Games.
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to the original poster....

Try reflowing the solderjoints.

I once had a first gen AES board with a socket.... It worked flawlessly with the debug, 4x and the original AES bios..... When I installed unibios 1.3, it refused to work... I could still get the other bioses to work but not 1.3... Finalyy I added solder to the pins and it worked fine.... who knows.
 

omnedon

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That BIOS pinout is awesome information. :eek: If one of those could be posted for each (BIOS location) variant, it would go a long long way to saving other NEO's as well.

Just be careful to do no more damage. If push comes to shove, JMKurtz is very good at solving these problems, and is fast, reasonable and professional.
 

MKL

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omnedon said:
If one of those could be posted for each (BIOS location) variant

There's only 2 actually. What holds for 3-6 also holds for 3-5 (just checked) and 3-4, 3-3...The other variant is the early board NEO-AES where some of the chips are different (no NEO G0, etc.). Next time I have one I'll check the bios connections for that too.
 

omnedon

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I don't have enough AES's (right now) to do it, but if I get to it before you do, I will post the info. I'm pretty new at trace following, and find the traces pretty tough to follow in some instances. However, a repository of this info would be a HUGE boon to everyone, IMO.

I'm willing to spend some time on it when the opportunity arises. :)

I sent a board to JMKurtz that I may have been able to sort out myself, if I had this info (when a board has issues, it's a bad reference board). nevertheless, it's great to have Jeff around for when things get hairy. :)
 

RockstarRunner

Wind Jammin' All Night",
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IT LIVES!

Firstly I would like to thank Razoola for being there online while I spent a total of 6 hours debugging the problem. Secondly I would like to thank MKL for the line-out diagram from the bios chip, this proved invaluable for locating the problem, and it would not have been solvable without it. Thirdly I would like to thank my buddy Miikka for actually doing the surgery on the Neo.

There where infact 2 seperate problems with the socket install, first was a lifted connection from pin 19 of the bios, on the component side of the board, we noticed this as the connection from socket pin 19 to pin 62 of NEO D0 was not working. Second problem was the connection from pin 24 of the bios to HC259 pin 13, on the component side of the board, there is a direct trace to HC259 pin 13 (runs under the HC259), there was a clear gap between this trace and pin 19 of the socket directly underneath the socket plastic, we made a bridge for that, and now all is well.

I would like to state that there are some golden pieces of information posted to the Tech support board that need to be linked in a sticky! The line-out information in this thread for instance, aswell as the RGB bypass info I collected from MKL and posted.
 

omnedon

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Whenever I see gold like the BIOS pinout posted in this thread, I save it to my computer immediately. It's GOLD I tells ya!

And congrats on the fix!! :multi_co:
 

Tiptonium

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omnedon said:
Whenever I see gold like the BIOS pinout posted in this thread, I save it to my computer immediately. It's GOLD I tells ya!

And congrats on the fix!! :multi_co:

Definitely GOLD!!!! It would be cool to have this info for all models.
 

Razoola

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Indeed, If anyone has the same info for the AES models that have the BIOS above the cart socket instead of the right side then that would be great. Chances are that all traces lead to the same places but its nice to be 100% sure.

Raz
 

MKL

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More trace info added to the above post. NEO-AES3-4 is confirmed to be the same as NEO-AES3-6.
 

Razoola

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Dam I missed that you had updated the pinout chart. I had to discover those Neo E0 traces on the Bios address lines last night to get a memory card working correctly.

Raz
 

channelmaniac

Mr Neo Fix-it
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Guys & Gals...

Let me save you a bit of troubleshooting time...

When you desolder the old bios chip & pull it out, check ALL of the pins of that chip for any pieces of copper. If you see ANY pieces stuck to the pins of that chip then you will need to do some kind of repairs.

If you aren't very skilled at soldering or desoldering then take the easy way out and use a tiny pair of dykes/cutters and cut all the pins off of the old BIOS chip close to the body of the chip. This way you can heat up the solder and pull each pin out individually. After this is done you can desolder the holes and put a new socket in.

Make sure you use a good quality socket, either machine pin or double-wipe. I would recommend against getting a single-wipe socket.

If you are unsure in your soldering skills, find someone with a professional soldering/desoldering station to help you.

RJ
 
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