VOGONS


First post, by Viserion

User metadata
Rank Newbie
Rank
Newbie

In addition to 2 retro systems I wanted to add a 486 dos machine.

As desk space is at a premium(I have waaaay to much stuff 😀 ), I went out and looked out for a Single computer board, as I have an Amiga 2000 that has passive ISA slots I can use it on.

SBCs are generally ludicrous expensive, but did managed to get one that was untested, and reasnoable cheap.

Tested it with a pentium MB(MALA5A) where I had removed CPU and ram.
Have done this before with a PIII SBC before, and this worked fine doing it the same way.
As it doesn't fit that well in my A2000, as the propertary Zorro slots are behind the ISA slots, and blocking PCI and capacitors on that card.
It was also a little too fast for my use.

Anyway, back on track, I tried to turn it on in a bit convoluted way.

Thew card is a 486/5x86 SBC Ver:G9 with a ALI M1989 chipset.
Not been able to find a manuaøl for my card, only a few that is close to the same layout. That means I don't know if the jumpers are set correct.

It's a "IT''S ST 486 DC-100" cpu on the card, and ny first question if is anybody has a manual or know the jumper settings for this.

Second is that the card has a AT style power connector.
Bought a ATX to AT, and with two PSU connected.
One on the MB, and one on the SBC card I tried starting it up, but no reaction on screen(SBC has an inbuilt vga card, but can't remember the type however).
In the manual I mentioned before I did find a pin overvirew over the AT connector, and from the looks of it, it's the P8 that should be connected, and that is what I tried.
CPU does get a little warm when turning it on, but well whitin what one wouyld expect.

I originally wanted to connect a ordinary molex connector by making an adapter out of the AT to AT adapter I bought, but need help figuering out how to make one, as there are more pins to the AT connector than a molex connector.
Just do not wish to make a fire ou of all of this 😵
So that is my second question.

Reply 1 of 14, by keenerb

User metadata
Rank Oldbie
Rank
Oldbie
Viserion wrote:
In addition to 2 retro systems I wanted to add a 486 dos machine. […]
Show full quote

In addition to 2 retro systems I wanted to add a 486 dos machine.

As desk space is at a premium(I have waaaay to much stuff 😀 ), I went out and looked out for a Single computer board, as I have an Amiga 2000 that has passive ISA slots I can use it on.

SBCs are generally ludicrous expensive, but did managed to get one that was untested, and reasnoable cheap.

Tested it with a pentium MB(MALA5A) where I had removed CPU and ram.
Have done this before with a PIII SBC before, and this worked fine doing it the same way.
As it doesn't fit that well in my A2000, as the propertary Zorro slots are behind the ISA slots, and blocking PCI and capacitors on that card.
It was also a little too fast for my use.

Anyway, back on track, I tried to turn it on in a bit convoluted way.

Thew card is a 486/5x86 SBC Ver:G9 with a ALI M1989 chipset.
Not been able to find a manuaøl for my card, only a few that is close to the same layout. That means I don't know if the jumpers are set correct.

It's a "IT''S ST 486 DC-100" cpu on the card, and ny first question if is anybody has a manual or know the jumper settings for this.

Second is that the card has a AT style power connector.
Bought a ATX to AT, and with two PSU connected.
One on the MB, and one on the SBC card I tried starting it up, but no reaction on screen(SBC has an inbuilt vga card, but can't remember the type however).
In the manual I mentioned before I did find a pin overvirew over the AT connector, and from the looks of it, it's the P8 that should be connected, and that is what I tried.
CPU does get a little warm when turning it on, but well whitin what one wouyld expect.

I originally wanted to connect a ordinary molex connector by making an adapter out of the AT to AT adapter I bought, but need help figuering out how to make one, as there are more pins to the AT connector than a molex connector.
Just do not wish to make a fire ou of all of this 😵
So that is my second question.

Post some good quality pictures of it.

Reply 2 of 14, by Viserion

User metadata
Rank Newbie
Rank
Newbie

Here are some pictures of the card.

Tried searching for manual, but only ones where AT connector is placed diffrently, and most of the jumpers as well.

Attachments

  • Image00005.jpg
    Filename
    Image00005.jpg
    File size
    643.97 KiB
    Views
    1169 views
    File license
    Fair use/fair dealing exception
  • Image00004.jpg
    Filename
    Image00004.jpg
    File size
    571.28 KiB
    Views
    1169 views
    File license
    Fair use/fair dealing exception
  • Image00003.jpg
    Filename
    Image00003.jpg
    File size
    588.93 KiB
    Views
    1169 views
    File license
    Fair use/fair dealing exception
  • Image00002.jpg
    Filename
    Image00002.jpg
    File size
    609.95 KiB
    Views
    1169 views
    File license
    Fair use/fair dealing exception
  • Image00001.jpg
    Filename
    Image00001.jpg
    File size
    691 KiB
    Views
    1169 views
    File license
    Fair use/fair dealing exception

Reply 3 of 14, by Viserion

User metadata
Rank Newbie
Rank
Newbie

Here are the last picture. Should have gotten pictures of the entire card.

Attachments

  • Image00007.jpg
    Filename
    Image00007.jpg
    File size
    327.04 KiB
    Views
    1168 views
    File license
    Fair use/fair dealing exception

Reply 4 of 14, by Viserion

User metadata
Rank Newbie
Rank
Newbie

Had a bit of success with this card.Cut off a little bit of the PCB where the ram slots are, and after plugging it in my Amiga 2000 I got a beep, and monitor turns on, but no picture is shown.
Only black screen.

I needed to put the single ram stick I have been using, into the second(closes to the CPU) ram slot for it to get this far.

Then I inserted a ISA graphic card, and I also got picture.

The unresolved issues are that internal graphics is not working, and that even if I have plugged in a keyboard in PS/2 contact, it isn't detected.

I found a manual to ftp://ftp.emacinc.com/LegacyProducts/SBC/ a similar card namly the SBC-455, and even if there are likness in the layout f the PCB, there is enough difference that it's not usefull, as the jumpers are placed diffrently, and layout is diffrent as well.
It might be the PS/2 port and internal graphics card is turnes off this way.
The manual for the other card, does mention that one can use a "PS/2 keyboard and mouse in one cable", and maybe getting that will cause the keyboard to be detected.

Battery is naturally also dead, so need to get hold of a new one.

Reply 5 of 14, by Viserion

User metadata
Rank Newbie
Rank
Newbie

Took a bit of time, but did get the PS/2 splitter cabel, but both keyboard and mouse are not detected.
No lights or anything.

I have tested these on a different PC, and they work there. Also tested different keyboard but no result.

Played around with different jumper settings, and even if I have reset it to how it came to me, it now identeifes as a 386 66MHz 😕
It also boots up without the AT P8 connector attached, so maybe that was needed for the inbuilt graphics, that don't work anyway.

Searched ebay for isa ps/2 connector boards, but couldn't find any.
Only PCI ones, and as this is a ISA system only it won't help me at all.

Any other way of getting around this?
Annoying to have all I want, only to be utter useless, as keyboard won't work.

Reply 6 of 14, by dionb

User metadata
Rank l33t
Rank
l33t

The power connector is an 'aux' power connector, not the basic P8/P9 one. An SBC like this gets its primary power via the ISA bus, the AUX tops it up if needed. I've run Pentium-class boards off ISA alone, so would be surprised if the AUX is needed unless you have other power-hungry cards on the same ISA bus.

As for the VGA, it's a Chips & Technologies chip that can do output to either an analog VGA connector or a digital flat-panel (that white connector on the PCB immediately above the chip). Quite possibly it's jumpered to output to that, which would explain why you're not getting anything out of the VGA connector.

With the keyboard I'd recommend keeping it simple: just a single PS/2 keyboard until you get that working. Combo ports always accept a single keyboard too (the mouse signals go over otherwise NC pins). No clear suggestions about how to get that single keyboard working. Perhaps someone tried hot-plugging it, blowing an SMD fuse. Check on the SMD bits around the PS/2 port...

Reply 7 of 14, by Viserion

User metadata
Rank Newbie
Rank
Newbie

The VGA output doen't really matter, as I have another ISA card that do work, but likley you are correct about the LCD/VGA bit.
As manual is not to be found anywhere it probably will stay that way.

Looked around the PS/2 connector, and try to reflow most of them.
Nothing that is obviously broken, and I could try replacing them had I known the value.
Some has value written on them, but others have no markings at all. That makes it difficult to replace them.

Reply 8 of 14, by Viserion

User metadata
Rank Newbie
Rank
Newbie

Searched around a bit again today, and in addition to desolder the flat Dallas battery, I might have found an incling of what the problem could.

I did continuety measuring that looked to me like a resistor excpet being green and lacking stripes.

Turns out it is a LF3A fuse, and when still conected I couyd measure continuety from one side of the fuse, and not the other.
When I soldered it out, it was the same when using my multimeter.

My question now is that since I don't have the correct fuse in that format, could I use a 3A fuse for cars, and solder it in and see if it works?
I think I have one of those around here somewhere.

I am the first to admit that I don't know very much about these things, that is why I ask before I try.

Reply 9 of 14, by Viserion

User metadata
Rank Newbie
Rank
Newbie

Used a 2A fuse, as I couldn't find a 3A one, and when I turned it on, keyboard is working.
So it was that fuse that had blown.

Ordered some new ones from China, so it will take a while before I get them.

Only oddity is that keyboard is not working when using ps/2 splitter, but optical mouse will lit up.

Tried connecting oposite of what label says, and keyboard is working again.
Not tested the mouse, as I havn't connected a harddrive to it.

So if I can find out how to turn on the graphics chip it would be a fully working board again.
It even identifies as a 486 100MHz again.

Reply 10 of 14, by whitepawn

User metadata
Rank Newbie
Rank
Newbie

Hi,
It will be a necropost but could you please dump bios file?I have a similiar hardware in this post which i don't have a bios for it.
PC420-G2 Single board computer manual and Troubleshooting
Thanks in advance.

Reply 14 of 14, by whitepawn

User metadata
Rank Newbie
Rank
Newbie

mt777,
I just wanted to confirm jumper settings along with my board thats why i asked for a picture. Most of "486/5x86 SBC ver g6" pictures onlne are have no cpu installed on board and installed ones are covered by a heatsink and also a not known working device.

Anyway bios dump will be very useful if you can share.