SLOT-6 dead? help! (^_^)

massimiliano

massimiliano

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Hi everybody, here what happens when I power up my fresh 6-slot:

6slot.jpg



HUmmm, it happens with cart inserted (ie slot 1) and without.

The screen flaps, but in the pic is framed of course.


I'll reserve a play on each of the slot for who can help me!

Thanks ;)
 
Konig

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This will be of no help, but 6-slot machines are known for having issues... for some reason they are problematic while all the other 1,2,and 4 slot machines work great.

good luck
 
andy251203

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Check your +5 volt line on the board (not on the harness) to see if its actually getting 5 volts. I had to crank my voltage up a tad when I first got my neo.
 
massimiliano

massimiliano

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andy251203 said:
Check your +5 volt line on the board (not on the harness) to see if its actually getting 5 volts. I had to crank my voltage up a tad when I first got my neo.
Click to expand...

Ok here a quick update:


it thick the sound (before I tried with speaker volume at zero)

Now a couple of times it goes the the green screen typical of the mvs boot, but it stucks there.

it's not always this way, as other times it stucked on the pic I posted (it even changed state from that to the green screen!)

:conf:

btw I tried raising +5 trottle to max but nothing...

Edit:

as i said it's a 6 slot, I even tried removing the two-wires connector (balck and red) between the two boards and it's the same... dubt it's a problem of the carts upper board.
 
Last edited:
channelmaniac

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When you say the screen "flaps" do you mean it flickers every couple of seconds and is there a repeating 'pop' sound out of the speakers to go along with it?

If so, the problem is a dead board. More specifically, the CPU can't get going enough to reset the watchdog timer and the watchdog is constantly resetting the CPU in a vain attempt to get it to start.

It can be caused by a bad BIOS chip, BIOS chip socket, CPU, Work SRAM, cut/damaged traces, bad control signals going to the Work SRAM or Backup SRAM, or a short in any IC that is connected to either the CPU's address or data bus.

RJ
 
channelmaniac

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Sticking on the green screen is indiciative of a calendar error. I suspect you still have something else wrong besides that because a calendar error won't cause the garbage screen issues you are seeing.

I just fixed a board last week for a customer in Colorado that would reboot anytime you jostled the board. Sometimes it would boot back up, sometimes it would stick in a constant rebooting cycle, and other times it would come up with a calendar error. It turned out to be poor soldering on the Work SRAM.

RJ
 
massimiliano

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channelmaniac said:
When you say the screen "flaps" do you mean it flickers every couple of seconds and is there a repeating 'pop' sound out of the speakers to go along with it?
Click to expand...

Yes that's it.
I saw it became the green screen but still "flapping"

channelmaniac said:
If so, the problem is a dead board. More specifically, the CPU can't get going enough to reset the watchdog timer and the watchdog is constantly resetting the CPU in a vain attempt to get it to start.

It can be caused by a bad BIOS chip, BIOS chip socket, CPU, Work SRAM, cut/damaged traces, bad control signals going to the Work SRAM or Backup SRAM, or a short in any IC that is connected to either the CPU's address or data bus.
RJ
Click to expand...

Shit, doesn't sound good.

well I have a slot-1, I could try to swap the bios and see what happens right?
Herr how could I check work SRAM soldering? I mean where is located? (^_^!)

In case of death... MKL where are you? we need to talk! :)
 
massimiliano

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Ok here is the lower board:

board-6.jpg



Does it seems a regular one?

Can someone spot the part I should inspect!?

Really thanks
 
massimiliano

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Ok another quick update:

I swapped the bios and nothing changed...
the slot-1 with the bios from slot-6 works flawlessy.

The mistery goes on...

Edit:

I checked all traces I could find, but nothing seems wrong (like cuts or else).
Looking at the soldering joints seems are all ok too..
 
Last edited:
massimiliano

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channelmaniac said:
Send it to MKL since you are over in his area of the world.
Click to expand...

Yes I think I'll try to reach him somehow.. !

anyway here just one thing that surprised me:

cpu-6.jpg


I know this board has been repaired, but this is something good?
 
channelmaniac

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Looks like a factory patch job... although I have to say I've never seen that particular patch job on another board.

RJ
 
dogtoy

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What happens if you boot it with just the bottom board only? You should get the blue crosshatch screen. If not I would try swapping the BIOS. Just to see what happens.

I had this problem on my 4 slot and it turned out to be because the contacts on the BIOS were dirty. I reseated it and then it came up with a RAM error. Then I put a UNIBIOS in it and skipped the RAM error and all the games played with garbled graphics. So I replaced the faulty RAM and it has worked like a champ ever since.

cheers,
-DT
 
massimiliano

massimiliano

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dogtoy said:
What happens if you boot it with just the bottom board only? You should get the blue crosshatch screen. If not I would try swapping the BIOS. Just to see what happens.

I had this problem on my 4 slot and it turned out to be because the contacts on the BIOS were dirty. I reseated it and then it came up with a RAM error. Then I put a UNIBIOS in it and skipped the RAM error and all the games played with garbled graphics. So I replaced the faulty RAM and it has worked like a champ ever since.

cheers,
-DT
Click to expand...

thanks dogtoy.

So far I tested the lower board (completely removing the bottom one) and nothing changed.
I changed the bios with one from a slot-1 and nothing changed.
The removed bios of the slot-6 goes smooth in the slot-1 but not viceversa , so the bios chip is not the prob.

I cleaned the board/pins/chip/soldering etc.. but nope.
No visible ruined traces.
I'm sending it to MKL, hope he can do the magic trick :)

I'm sure the board take some punch during the shipment, so probably some soldering cracked or worst.. dunno.

I'll keep my finger crossed.:cool:
 
mainman

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Your problems seems to be associated with either the video ram or the custom LSPC-A0 and I am leaning towards the LSPC-A0. Give us a history of this board, has it ever work while in your possession?
 
channelmaniac

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mainman said:
Your problems seems to be associated with either the video ram or the custom LSPC-A0 and I am leaning towards the LSPC-A0. Give us a history of this board, has it ever work while in your possession?
Click to expand...

How can you say that? If it's stuck in watchdog then it's not even getting to check the video RAM or initializing the video...

Since he doesn't have the ability or tools to troubleshoot the digital logic he should send it to MKL for final diagnosis and repair.
 
mainman

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channelmaniac said:
How can you say that? If it's stuck in watchdog then it's not even getting to check the video RAM or initializing the video...

Since he doesn't have the ability or tools to troubleshoot the digital logic he should send it to MKL for final diagnosis and repair.
Click to expand...


A watchdog error can be caused by any failure of a sub system or its related logic channelmaniac on the data and address busses, its a wider error to troubleshoot than even the z80 error. It could be ram, rom, gating circuits, customs. I know from experience a problem with the lspc can bring up the watch dog and give the screen show in his pic. Although in my case the the chip just outright failed. If that area has problem you will also see horizontal lines if it just a trace issue but yes it would still boot to cross hatch if that was the case. Unrelated I even had the pro-cto fail on me.

It could be so many things I am just basically telling him to start where I basically found my solution which may or may not help him.


Before he send it out I say he should at least check for broken traces around the 68000 and ram at the very least if checking the lspc is hurdle.
 
Last edited:
massimiliano

massimiliano

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Thanks everybody for your help.
I'm sending it to MKL, as he's a pro and can take a look of the problem.

I ordered the board, and it arrived to me in this condition.
The guy who sold it to me said that it has been rapaired but for an audio problem.
Unfortunatly, the board was not well protected in the carton box of the shipment, and take some punch during travel.
In fact the screw holders (those in pink plastic you know) where all broken on one side, and th iron cover was bended. Initially I couldn't fit a cart cause the cover was decentered.

And that's it.... i trust the guy who sold me the boards, as there was also a slot-2 which goes smooth, and he's trying to manage the problem somehow.

HUmmm... hope it's just a stupid joint.
 
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