It looks like the main things happening on this card, are high speed serial controllers and a whopping 54 pcs of 41256 (256kb) ram units.
This would break down to 6 banks of 256kB with parity, 1,5MB ram.

Let's see...

FCC ID shows "IDE associates" as well, with a grant dated to April 14th, 1986. On the front there's a sticker with "Tele AT Max". IDE Associates cards usually were called something-or-other max, so I'm guessing that's its name. That's the good news. Bad news is that I don't seem to be able to find anything using that as search term. I also took a look at memory cards and I/O cards on th99, but nothing similar unfortunately.

Maybe someone else has a stash of memory card documentation, but I fear this needs reverse-engineering.

As for functionality:
- 2x serial UARTs
- one 26p parallel header
- a (proprietary) 44p header that looks like it could connect a daughterboard with extra RAM
- 3 rows of 17 256kx1 DRAM chips, i.e. 512kB per row, 1.5MB total (with 1:16 parity)

So not really that much going on, it's just 2x serial, 1x parallel and memory. Only question is whether it's extended or expanded memory. Given that this card pre-dates XMS 2.0 (from 1988), I suspect it's EMS.

44-pin IDE is real and carries power & ground, so that's a possibility for the header. The control circuitry is mostly on the hard drive/cd-rom in this era.

I second it as a EMS memory expansion board.

MikeSG wrote on 2025-02-04, 07:19:

44-pin IDE is real and carries power & ground, so that's a possibility for the header. The control circuitry is mostly on the hard drive/cd-rom in this era.

In 1986? This card pre-dates the IDE standard, let alone later derivatives like 2.5" laptop drives, for which 44 pin 2mm pitch connectors were used in the 1990s.

In 1986, RLL-encoded ST-412 was just replacing MFM encoding as the default HDD tech, both having 'dumb' drives and a 'smart' controller. The IDE and SCSI standards were finalized in late 1986, but wouldn't become common for some years yet. If a 1986 drive wasn't MFM or RLL ST-412, is would have been ESDI, which also uses separate control/data cables.

But regardless, take a look where the traces from the connector go. No drive interface would be multiplexed with the memory chips.

TTG wrote on 2025-02-03, 11:54:

Hello all, […]
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Hello all,

I have had this ISA card for quite some time but no matter how much research I've done i still don't know what it is,

In the pictures bellow it says it's from (ide associates inc) but I can't find much info on that company.

It looks like the card has 256k memory adds up to 9mb, also it has a lot of dip switches.

The card seems like it has a lot going on
Not much on the back. All though it does say,
(Component side) and (solder side) on the back and top.

Little bit interesting.

Anyways any info needed I will help, really want to know what this card could be.

Seems like a match... https://archive.org/details/idea-supermax/mode/2up

Good find PC Hoarder !

dionb wrote on 2025-02-04, 09:00:

In 1986? This card pre-dates the IDE standard, let alone later derivatives like 2.5" laptop drives, for which 44 pin 2mm pitch c […]
Show full quote

MikeSG wrote on 2025-02-04, 07:19:

44-pin IDE is real and carries power & ground, so that's a possibility for the header. The control circuitry is mostly on the hard drive/cd-rom in this era.

In 1986? This card pre-dates the IDE standard, let alone later derivatives like 2.5" laptop drives, for which 44 pin 2mm pitch connectors were used in the 1990s.

In 1986, RLL-encoded ST-412 was just replacing MFM encoding as the default HDD tech, both having 'dumb' drives and a 'smart' controller. The IDE and SCSI standards were finalized in late 1986, but wouldn't become common for some years yet. If a 1986 drive wasn't MFM or RLL ST-412, is would have been ESDI, which also uses separate control/data cables.

But regardless, take a look where the traces from the connector go. No drive interface would be multiplexed with the memory chips.

I was thinking back to an old 8-bit CD-ROM card I had. That was just buffer chips & a port.

It doesn't look multiplexed with the memory chips. It's maybe multiplexed with the large serial/parallel port.

The linked manual in the above post by PC Hoarder Patrol shows it is a 2xCOM +1xLPT + memory expansion with an optional daughterboard for even more memory; the diagnostic tool describes a 64k buffer used to testing the memory, so it could be similar to EMS, but this is not explicitly stated - and the use cases listed are e.g. custom printer buffers and a virtual floppy disk - I suspect it is using some custom way to swap pages, so maybe not compatible with EMS methods. There seem to be some custom software needed to control the card, in order to use the memory expansion.