The original also came with several expansion cards
An CGA or EGA or VGA card?

An I/O card (with extra memory ?)

And a controller card

I hope I will be able to use them in the new build

After many years I decided to buy a new board so this build can finally make some progress

The I/O board seems to be an Everex EV 173. I don't think documentation is available, but it seems to be an odd choice for a 286. Normally this type of card is used to expand memory in 8088 systems. My guess is that the onboard memory must be disabled, otherwise there would be an address conflict with the memory on your 286 board.

Well, its not exactly my choice. Its simply what was installed on the original NEAT bord when I got it. And I dont know if and how it worked on that board either. I actually have never worked on a board with individually socketed RAM nor have I ever used a PC where RAM expansions is done via ISA cards. I think the onboard memory is probably 1MB. So would you say without documentation its impossible to use that I/O board additional RAM expansion?

Isn't there a subforum for build logs?

The extra ram is probably 256kb. It’s not really usable on a 286 due to its 8-bit nature. I guess in theory if you disabled all but 256 or 512k on you 286 board you could use the card ram, but it would be super slow. Of course you’d need the documentation to configure the starting address.

so - the machine is alive - but I have a ton of new problems. The good thing is that the graphic card and the mainboard seem to work fine. That I/O board failed spectacularly with one of the small yellow caps making a firework. I think I wont use that board for now. However the biggest problem for now is the controller card.
It is too big! Its full lenght anyway but it is too broad fro the case.

Im really dissapointed.

Other things I noticed
- Dallas RTC fix seems ok and holds the time
- except for reset, I cant find any other headers for LEDs. Are those just missing or simply not labeled on the board?
- Due to the design of the board the graphic card wnt go into the first ISA slot - is this a problem ?
- Although I cant use the controller board anyway, I wondered - it has a header for a HDD but its not an IDE but much thinner - what is it and what kind of drive can you connect to such a controller?

Gratefull for any help suggestions questiosn or discussion

Hi again,

after I realized that the floppy disk controller is too big (full lenght but too broad) I decided to buy a new one.
It looks like new, but is not working at all (neither in this machine nor in any other).
I have a similar controller from another machine which addresses both floppy drives correctly - so the drives are most likely ok)
There are myriads of jumpers but of course, I dont have a documentation.

So far the drives are not even lighting up at all or testing during boot up. Am I doing something wrong? Are such controllers known to go bad (what would be the problem ?)
Would be grateful for any suggestions / controller documentation or how to tackle this problem.

thanks

You're going to need to figure out what the jumpers do. It's entirely possible that sections of the card have been disabled via jumper, and that is why it's not "working".
In my experience these cards rarely go bad, but we don't know it's history so maybe it really is fried.

I noticed the graphics card in there is also Everex. That's a big honking card. It has way too many VLSIs to be CGA. It is without doubt an EGA card. It also has the 15 pin analogue connector which implies it might be VGA, but all I could find on EV 673 is the TH99 page, which claims MDA, CGA and EGA. I've seen EGA-only cards with analogue connectors before, so this might be one of them.

According to this webpage https://www.dosdays.co.uk/topics/Manufacturers/everex.php

it is quite a versatile card (by 1987). it says:

EV-673 EVGA

Launched: 1987
Bus: ISA 8-bit
Support: MDA, CGA, EGA, VGA, SVGA

The EVGA was designed to provide full VGA capabilities to an IBM PC, XT, AT and compatibles, given that it was an 8-bit ISA card. It provided the standard VGA's 256 colours at 640 x 480 (out of a palette of 256,000) and supported all 17 VGA modes in hardware.

In addition, EVGA also supported:

512 x 480 in 256 colours for video capture1280 x 600800 x 600132-column text modePS/2, Multi-frequency, EGA, CGA and monochrome monitors

Like with the controller, I have no idea how to configure the graphic card, but right now its giving me a normal vga output, so I wont touch it.

Any suggestions how to approach that floppy controller? Im not very good at combinatorics, but just randomly changing jumpers seems to hold an awefull number of possible combinations...

I found this link

https://arvutimuuseum.ee/th99/c/I-L/21658.htm

and this one

https://www.minuszerodegrees.net/manuals/Kouw … s%20missing.pdf

the FCC ID is partly identical (KW-557A). I tried about 50 different combinations using the documents as a rough guide, but still get FDD / HDD controller failure message ?!

Ok - big step forward. I found the same card with good pictures on ebay and simply copied the jumper config. Now FDD and HDD interface work. The only thing thats not enabled is the mouse port. Hach - cant have everything...

Now I even found the proper description of the card.

https://arvutimuuseum.ee/th99/c/I-L/21402.htm

You can try the extended EV673 modes in MODETEST.EXE from Pizazz Plus 2.0...

Hi again, Im still facing a problem installing a mouse at the serial port. I feel Im very close, but its not working yet.
With the correct manual, I can set the jumpers correctly:
https://arvutimuuseum.ee/th99/c/I-L/21402.htm
to install a mouse, I have 2 connectors (J4 and J5) available that I can also switch. Jumper setting is adjusted for serial port 1 or 2.

I have a original (working) serial mouse with its original driver and also a microsoft ps2 mouse with adapter. Port addres is recognized correctly and all drivers report that the mouse is correctly installed (COM1 - 3F8h). NSSI also reports serial port / mouse at the correct address. Ctmouse driver as well. The only problem is - its not working. Any ideas would be appreciated.

Regarding the Pizazz Plus - does this software "sets" the different video modes without me adjusting the dipswitches on the card? Also - I thought for example CGA mode needs a dedicated cable / monitor ?

Thanks to everyone for any help

Aui wrote on 2024-05-10, 22:52:

Hi again, Im still facing a problem installing a mouse at the serial port. I feel Im very close, but its not working yet. With t […]
Show full quote

Hi again, Im still facing a problem installing a mouse at the serial port. I feel Im very close, but its not working yet.
With the correct manual, I can set the jumpers correctly:
https://arvutimuuseum.ee/th99/c/I-L/21402.htm
to install a mouse, I have 2 connectors (J4 and J5) available that I can also switch. Jumper setting is adjusted for serial port 1 or 2.

I have a original (working) serial mouse with its original driver and also a microsoft ps2 mouse with adapter. Port addres is recognized correctly and all drivers report that the mouse is correctly installed (COM1 - 3F8h). NSSI also reports serial port / mouse at the correct address. Ctmouse driver as well. The only problem is - its not working. Any ideas would be appreciated.

First and foremost, check the serial port with CheckIt 3.0, and a loopback plug:
http://www.hardwarebook.info/Serial_Por ... 9_CheckIt)
http://www.hardwarebook.info/Serial_Por ... 5_CheckIt)

Regarding the Pizazz Plus - does this software "sets" the different video modes without me adjusting the dipswitches on the card? Also - I thought for example CGA mode needs a dedicated cable / monitor ?

https://arvutimuuseum.ee/th99/v/E-H/52365.htm

Looks like a normal early SVGA, after all.
No need to touch the DIP-switches, modes 0..19 should just work with any (S)VGA monitor.

I'm not sure about the extended modes...
800 x 600 x 16 usually uses 56 Hz refresh, and 36 MHz pixel clock.
But there's no 36 MHz crystal on that Everex, there's a 35 MHz one instead - which suggests non-standard timings, possibly incompatible with typical monitors.
640 x 400 x 256 and 512 x 480 x 256 may be problematic as well - early SVGA cards often run such modes below VGA frequencies, also incompatible with common monitors.

Overall, don't worry if those modes won't work for you - such problems may be normal, and impossible to fix with jumpers/DIP-switches.

Hi again,

tried the Checkit software. I dont have a loopback plug but it is still testing the com1 port and all tests are passed. Ct mouse also comes with some test utilities. They all see a mouse at com 1 (IRQ4) at 3F8H.
They also see for example if IRQs are wronly jumpered (i.e. if multiple options are set.). However, cursor is not moving a bit. I upload again my current jumper config picture the way I think it should be set. Maybe I have missed something.

Here the diagram again:
https://arvutimuuseum.ee/th99/c/I-L/21402.htm

thanks

Wait...
You have both SERIAL PORT 1 and SERIAL PORT 2 configured as COM1 (3F8h)...
change JP6 to COM2 (2F8h) - Pins 1 & 3, 2 & 4 closed.

TADAAAA...and it WORKS !!!

its incredible - I think I have never been happier seeing a mouse cursor move.

Thank you sooo much!