486 EISA system

Chuck Guzis cclist at sydex.com
Wed Oct 4 10:42:10 CDT 2006

On 10/3/2006 at 9:08 PM Teo Zenios wrote:

>Another Ebay find came in today, a 486 EISA motherboard and 5 cards.
>The motherboards seems to be this model:
>http://artofhacking.com/th99/m/U-Z/31111.htm , but I can't find a company
>name on it anywhere. It has 8 EISA slots seems to be setup for a 486 DX.
>it looks like there are 2 DALLAS real time clocks on it, and the machine
>complains the eisa config battery is low. Are there any cheap hacks to get
>around this?

Only one of these is an RTC chip, the other (DS1225V) is an 8Kx8 NVRAM.  I
wonder if it might be simplest to replace this one with a similar FRAM
(Ramtron FM-1608) and be done with the battery issue, at least on the one
chip.  The Ramtron chip is also cheaper than NOS DS1225Vs, BTW.  You might
also be able to carve into the encapsulation with a Dremel to get at the
lithium cell as a very cheap dodge.

As far as the DS1287 RTC, it's been discussed on the list before (you can
carve into the epoxy and tie into the lithium cell contacts, or you can
just replace the chip).
http://www.maxim-ic.com/appnotes.cfm/appnote_number/503 has notes on


>The cards that came are the following (all EISA):
>HP 10Mb and 100Mb network card has a HP/AT&T 100VG chip
>Aview 2e Video card, 1MB VRAM
>Adaptec AHA-2740 and AHA-2740A SCSI 50 pin (no floppy controller) SCSI
>Mylex DAC960-1/2 caching controller card with what looks like 16MB (maybe
>4MB) of RAM installed (4x30 pin). The card has a nice big Intel i960 chip
>(first one I have).
>When the machine boots I don't see any info on what processor the system
>has like you would normally see on a 486 system, and no BIOS screen for
>the SCSI cards comes up either (not that there is anything connected to
>them). The caching controller is odd looking because of the large SCSI
>connectors ( there appears to be a 50 pin SCSI internal , and 2 68 pin
>SCSI (one looks like a normal 50 pin but its long and has 68 pins, the
>other looks like a 68pin connector on newer cards but the pin spacing
>makes it look 3x longer). Is this a raid only card and do I need special
>cables for the 68 pin connectors or are there adapters for these?>
>I never used an EISA machine before (one of the reason I snagged these)
>and was wondering if there is anything special about them. Is there a
>standard configuration utility for EISA cards or do you need to find one
>for each card?
>Also since this machine is all EISA slots would putting an ISA card in one
>of them slow the BUS down? I need to find an EISA floppy and I/O card to
>complete this, anybody have one they don't need?

More information about the cctalk mailing list