Poorly AES Console help

[Beaps]

I finally picked up an AES Console as I have never owned one only MVS.

I got it cheap as I knew it needed fixing. I have looked at the board but it looks pretty clean. The only problem I had was the resister near the on/off switch had solder on it for some reason & the legs was bridged. I separated the contacts & now it switches on/off fine.

The next problem I have is there are sprites missing (see pic). The sound plays fine.

Any ideas on where I should be looking would be a massive help.

 

[greeneye8181]

Check out my thread. Xian and smkdan had some great info.
Your problem seems to be the "jailbar" issue. Not sure though look at the link smkdan provided. Hope this helps.

 

[Beaps]

Ok I looked around the two points mentioned and didn't find ant broken traces. I did notice that the chip in place HC259 had been replaced. Under further inspection I noticed a broken trace. Excited I quickly fixed it and...... Nothing same screen, sprites missing :-(

 

[Beaps]

Neo Geo forum, Neo Geo Console, someone must be able to give me a few pointers please.

 

[Hans Grösse]

Mail it to lukemorse1. He fixes these things.

 

[GadgetUK]

Not sure if your AES has a ROM socket? I would start by programming the diag BIOS and plug that it to check different RAM types.

 

[GadgetUK]

Also see this wiki page! It can help identify which area might be related:-

https://wiki.neogeodev.org/index.php?title=Graphic_glitches

 

[Beaps]

The rom Bios is socketed mate. I have a piggy back IC holder on the chip and tried the Unibios mod, but it dosnt fire up all in this setup, just this pic.

With cart inserted


No cart inserted

 

[GadgetUK]

Those pics with Unibios installed look very very strange! I wonder if the AES has a different ROM pinout, or perhaps someone bodged up the mod to allow a unibios originally. I would start by checking all the connections to that bios - there should be a switch to toggle between the rom on board and the 'piggybacked' eprom? If there's no switching mechanism the AES will be trying to boot from the original rom and the unibios at the same time.

Once you get unibios working, see if that reports any errors, if not then program a diag bios, then fit that and see what if anything fails tests. If it passes all then you are likely looking at a damaged track or something related to cart io.

 

[Beaps]

There is no switch mate, its a leg up jobbie

http://www.mmmonkey.co.uk/snk-neo-geo-aes-unibios-install/

Also I anit got a burner so I don't own a Diag Bios

 

[pulstar]

Hey Beaps, if you need/want a diagnostic rom send me a PM and I'll send you mine.

 

[Beaps]

Haha small world hey mate, let me drop you a pm :-)

 

[pulstar]

I get around...

 

[GadgetUK]

Hey Beaps, if you need/want a diagnostic rom send me a PM and I'll send you mine.

Regards the 'leg up' mod, it still need something doing to switch ROMs. From your pics it appears it was working with bios already on the board, and presumably has a socket piggybacked onto that bios? So just plugging in unibios isn't enough!

 

[Beaps]

Yer I gotta socket soldered on the original bios, a cut pin 2, resister from pin 40 to pin 2, wire from pin 2 to pin 20.

Again I spent over an hour looking for bad traces last night (started o see traces on the back of my eye lids, lol), i cannot see anything obvious. I cleaned the cart edge so it looks brand new, and I am 100% sure its not the cart connector as the theeth look good.

 

[Beaps]

OK so tonight I decided I would take out the old AES bios & install an IC Socket. I took out the old bios and low & behold, under it was a dead trace. I patched the trace and inserted the Unibios. The chip below had had a repair in the past & I cant for the like of me which pin on the bios they went. Can someone please confirm.

 

[GadgetUK]

well the 3 pins (with the green wires) there on the NEO-EO are 16,17 and 18 which are:-

16 A6
17 A7
18 A8


I think, from the diagram they go to:-

16 (A6) goes to 27 on SP1
17 (A7) goes to 28 on SP1
18 (A8) goes to 29 on SP1

Confirmed on my MV-1FZ

 

[Beaps]

Brilliant, thanks. I'll try that & report back

 

[Beaps]

OK thanks to GUK I rewired the 3 wires back & I am at this point, nearly there!!

 

[GadgetUK]

Sounds like a bodged ROM upgrade to me - I would check the schematics for the MV-1FZ, see where the SM1 chip is, you need to check the remaining pins on the BIOS to make sure they are going to all the relevant places. If you can't follow the diagram I can give you a hand.

EDIT: I don't mean by you btw! I mean by the original owner. It's possible that's all that's wrong with it. You will know more once you get past the BIOS error.

 

[GadgetUK]

Any joy with this? Do you want me to do more pinouts for you to check on the BIOS?

 

[Beaps]

Mate that is super kind of you but after I hit a brick wall I sent it off for repair. Thanks for all you help tho mate, let's see what happens