Does the board also have sockets for 41256 dip chips? Usually you have to install one or more of those along with the 44256 modules (at least, you have to, if using dip chips on my 286 motherboard, rather than the simm slots)

The information of this board i get from here..

http://stason.org/TULARC/pc/motherboards/A/AU … -XT-BXM-12.html

Its almost the same board. Only some headers for the front display (Pwerled, Reset ect) sitting on an other place..
So i red in that manuel i need to fill up bank 0, bank1, bank3 with 44256 chips.. So i did that..

I already orderd an Diagnose POST card for it.. I think the problem could maybe the VGA card. But iam not sure about that.

I have some picture to clear it out more:

The memory banks: (those tiny sockets are for parity only!)

The memory chips i got. They are mitsubishi 20-pin dip M5M44256BP they are rated at 80NS! (because theres a -8 behind it)
Having 8 of those, the other one was already placed in the motherboard DIP socket..

Putting the memory in!! It was a little bit a hassle to get them in the sockets but all pins are in the sockets!..

I need to use a little fork to get those chips easily out. Otherwise bending those little tiny pins..

The memory is in!!

PICTURES ARE CLICKABLE!!

I know nothing of XT computers but would try to search for what those beep codes mean.

Do not have documents of this board.. The only i could find was on stason.org..
But i only need to wait on an diagnose POST card, then i can could further.. (i ordered it today)

Really the only i could give you is this link.

http://books.google.com/books?id=69648Y1sOewC … epage&q&f=false

It is a googlebook preview of "The bios companion" a book about the bios. There is a chapter called Nasty noises and its all about beep codes. There is nothing i can see about FLYTEK ST-12 though. Most of the chapter is available from google book, but there are some bits missing, sorry cant do anything else.

Today i received the memory 44256 DIP, 8 pieces from them for 1MB of total memory.(they are 80NS chips) I think that will be 640KB of normal memory and 384KB of EMS memory..

No that will be 640kb conventional, and 384kb of upper memory. You'll need an expansion card for EMS.

First thing to check is all the switches/jumpers. On the diagram you linked, there is a jumper for 0/1 WS, try setting it to 1. Also, since you are using 44256 DIPs you need to disable parity, so make sure that jumper is set correctly. You also need to set switches A/3 and A/4 both OFF for 1MB of RAM.

So i maybe need 64k memory as well? Like this:

In this manual:

http://stason.org/TULARC/pc/motherboards/A/AU … -XT-BXM-12.html

It will saying that he`s having 640KB of memory..

That's just a different configuration. If you don't want the full 1MB you can use the 4x 44256 chips in bank 0 & 1, and the 4x 4464 chips in bank 2, for a total of 640KB conventional memory. Assuming the diagram on stason is accurate for your board.

One thing you could try is taking the 44256 chips out of bank 3 and see if it boots with 512KB.

You may want to take this to http://www.vintage-computer.com/vcforum/forum.php and see if they have any suggestions because they tend to deal with t his older stuff more than on this site.

Robin4 I had bought the same board from the same seller a year ago. Mine worked fine. First tell us what kind of video card did you use. As far as the ram chips are concerned, I remember using 8 chips for a total of 1MB, which I had from a broken ISA svga card. Also keep in mind that you need a special keyboard for that. The AT keyboard although having the same DIN connector as the older pc-xt keyboards, is completely different. Some older keyboards used to have a switch to select between pc - at or 80286 - 8088, etc. That's the best one to use.

@ Markk

Thx for the reply. Question; Are you the guy from ebay ive mailed to?

The videocards i only have laying here are a Trident TVGA8900cl with 512KB memory on it.. It looks like it would use the same type of memery i guess.
Its a 16-bits VGA card and from the documents on the internet it should work as an 8-bit card aswell.. Trying to hardforce it to use in 8-bit mode. But my monitor(old 14 inch hansol TFT) doesnt react on this card on this XT motherboard. But recently this Trident one worked perfectly on a system that i bought from a company secondhand on a 386 motherboard.. Build year was 1992..

The other card that i have here is a STB Microeletronics (i guess the microelectronics) Nitro VGA 16-bit ISA card..But this is a active 16-bit i guess so i cant set it to 8-bit mode, because there are no jumpers for that. It had SOJ memory on it 1mb in size..

So these are the only cards that iam having here..

What iam thinking to going do now..

-Yesterday i ordered a cheap POST Diagnose card (isa /pci one) So to easily find the problems..

- I think the cards i have laying here shouldnt work.. So i have to buy some 8-bit VGA cards.to try does out.(the ones i have, i cant use it)

- I think the memory that ive bought are the good ones, because i heard a reboot sequent(ence) because of its reboot loops.. Think the turbo led goes off and then rebooting, then i hear the pc-speaker blieping and then rebooting again (i think because of the AT-keyboard i guess)

And the problem of the XT- keyboard..

Iam thinking of buying an EEPROM programmer.. Because last time i got a lot of flashing tasks, and its easier to have one here..

I can get an 27256KB C-mos of an old modem card i have laying here. I trie to get the hand on the orginal juko ST-12 bios.. And flash this in the other ones c-mos chip and trying that one out if the bioses are almost the same..
When i looked at the bios.. of those JUKO ST and clone (FLYTEK) ones.. i see the differents on those..

The FLYTEK BIOS HAS VERSION 2.20 ON IT. THE JUKO ST-12 BIOS HAS A VERSION 2.30, SO MAYBE THAT JUKO ST ONE SHOULD WORK WITH AT KEYBOARDS!!

First, I'm not the guy from ebay. At least I didn't have any mail so far.

So let me see. By reading your description, I think you might have to try with a different video card. If I remember well, not all of my ISA vgas would work on that. I found just 2 that would be fine. The trident 8900 might not work I think, but an ancient t8800 with dual output (vga and cga/ega) I had worked. The same for another chips and technologies based vga. Also try to fiddle with the switches 5 and 6.

Rebooting all the time after a while is normal. That happens all the time when there isn't a floppy drive atteched. And in the beggining sometimes the turbo led goes off and on again. I think it also went off whenever the system accessed the floppy drive. But then I started using the 2M xbios utility, so as to be able to use 1.44MB floppies, and when I load that, the turbo led stays on all the time.

Finally about the keyboard, I'm pretty sure that you need an XT compatible one. I'll check my board's bios version, and I'll report later.

edit : I found my nec pc build thread, here :
My "new" NEC V-20 based PC
I can see that my bios version is 2.20.

Markk wrote:

First, I'm not the guy from ebay. At least I didn't have any mail so far. […]
Show full quote

First, I'm not the guy from ebay. At least I didn't have any mail so far.

So let me see. By reading your description, I think you might have to try with a different video card. If I remember well, not all of my ISA vgas would work on that. I found just 2 that would be fine. The trident 8900 might not work I think, but an ancient t8800 with dual output (vga and cga/ega) I had worked. The same for another chips and technologies based vga. Also try to fiddle with the switches 5 and 6.

Rebooting all the time after a while is normal. That happens all the time when there isn't a floppy drive atteched. And in the beggining sometimes the turbo led goes off and on again. I think it also went off whenever the system accessed the floppy drive. But then I started using the 2M xbios utility, so as to be able to use 1.44MB floppies, and when I load that, the turbo led stays on all the time.

Finally about the keyboard, I'm pretty sure that you need an XT compatible one. I'll check my board's bios version, and I'll report later.

edit : I found my nec pc build thread, here :
My "new" NEC V-20 based PC
I can see that my bios version is 2.20.

Hey thanks for your reply, you gave me a lot more information about this board.. Very nice you rebuild that ATX case to a AT one.. Nice build over there..

I have some questions..

In your thread you mentioned about that real time clock thing.. do i really need that thing to let my XT motherboard work?(i dunno where that real clock thing is for) Is it for saving the bios information or something or is it just a clock for the bios time settings?

How can i regonize an real time clock for an XT motherboard? Are those always sitting on graphic cards / add-on cards?

How can i regonize if iam going to look for an XT keyboard? Does all does XT motherboard need XT keyboards?

Robin4 wrote:

I have some questions..

In your thread you mentioned about that real time clock thing.. do i really need that thing to let my XT motherboard work?(i dunno where that real clock thing is for) Is it for saving the bios information or something or is it just a clock for the bios time settings?

No, it's not necessary for the system to work to have the RTC. Back then, the pcs didn't have that clock, so the only way to keep the correct date and time(if needed) was each time you boot to use the time and date dos commands.

Robin4 wrote:

How can i regonize an real time clock for an XT motherboard? Are those always sitting on graphic cards / add-on cards?

Yes, usually memory expansion cards and multi i/o cards had a RTC. You can tell if it's like that, if you see a battery socket for a 2032 or larger battery on the card.

Robin4 wrote:

How can i regonize if iam going to look for an XT keyboard? Does all does XT motherboard need XT keyboards?

I'm afraid yes, you have to look for a keyboard. You may search either for a "dual" keyboard having selectable AT-XT operation with a small switch on the bottom, or a specific XT type(that may be harder to find). A correct keyboard will blink all the three leds for a moment when you power on the system, whereas it won't do that when connected on a more modern pc, and vice versa.

Can somebody tell me. I found an picture on ebay. I want to ask, is this that famous switch on a XT / AT style keyboard:

Robin4 wrote:

Do not have documents of this board.. The only i could find was on stason.org.. But i only need to wait on an diagnose POST card […]
Show full quote

Do not have documents of this board.. The only i could find was on stason.org..
But i only need to wait on an diagnose POST card, then i can could further.. (i ordered it today)

PCI card for an XT motherboard...?

There's an ISA edge connector on that card. 🤣 It's one of those deals where it's ISA on one edge, and PCI on another.

Hahaha, wow.... note to self: do NOT post while on sleep deprivation. 🤣 🤣 🤣

Robin4 wrote:

Can somebody tell me. I found an picture on ebay. I want to ask, is this that famous switch on a XT / AT style keyboard: […]
Show full quote

Can somebody tell me. I found an picture on ebay. I want to ask, is this that famous switch on a XT / AT style keyboard:

Yes, seems like that. That's where many keyboards have the switch. You can also ask the seller if there is anything written close to that, in order to make sure it's what you're searching for.

I want to let you know that this motherboard has working... I bought an vga card for it and an XT keyboard.. Yesterday i have played some old games on it.
But missing an harddisk is very horrible to me..

Does anyone has STJUKO BIOS V2.30 for me?? I want to try it out on my motherboard.