Help need to identify 8-bit ISA Card

[Ketema]

Good day everyone,

Would anyone help if you know what this ISA card is used for (see attachment)? It has DB25 connector. The cpu on the card is Motorola 6809 found on the lower left corrner.

It looks like a serial card but there is way too much stuff on it to be a simple serial card. 

The card came out of my NEC PC with Intel 386 DX cpu.

Thank you!

[edavid]

Would anyone help if you know what this ISA card is used for (see attachment)? It has DB25 connector. The cpu on the card is Motorola 6809 found on the lower left corrner.

If that's an 8274 under the R6522, it's a synchronous serial card (for SDLC/HDLC etc.).

The card came out of my NEC PC with Intel 386 DX cpu.

If it was in your PC, why don't you know what it's for? 

[helius]

See this industry survey: Datapro Reports on PC and LAN Communications 1992
The card is called the "LinkUp 3270".

[squadchannel]

I found several magazine ads.
They seem to still be in business today.
I.T.I. INFORMATION TECHNOLOGY, INC. 56 Kearney Road Needham, MA 02194

[Ketema]

Would anyone help if you know what this ISA card is used for (see attachment)? It has DB25 connector. The cpu on the card is Motorola 6809 found on the lower left corrner.

If that's an 8274 under the R6522, it's a synchronous serial card (for SDLC/HDLC etc.).

The card came out of my NEC PC with Intel 386 DX cpu.

If it was in your PC, why don't you know what it's for? 

I will lookup SDLC. It looks like IBM's enterprise level serial communication from late 70s. I am only familiar with asynchronous serial communication.

FYI, I purchased the PC from garage sale so it wasn't mine until recently. It also came with token ring 16-bit network card.

I appreciate the response!

[wilfred]

SDLC is a largely obsolete protocol once commonly used to connect a remote terminal or a controller for a local cluster of terminals back to a mainframe. It was a synchronous protocol that you could use a modem link at say 9600bit per second which in the 90's you would lease from a telecoms supplier. It had other uses in IBM mainframe datacenters, but connecting remote offices was a major use.

This is a manual that describes more details https://archive.org/details/bitsavers_ibmdatacomptsJun86_2781553/page/n65/mode/2up
Synchronous Data Link Control Concepts GA27-3093

The 386 PC that contained it is period correct as the PC became common on desktops they replaced dedicated IBM 3278 and 3279 terminals.

That card is a historical relic not useful for anything other than its original purpose which was never in isolation from other hardware and software in the network.

[Ketema]

That card is a historical relic not useful for anything other than its original purpose which was never in isolation from other hardware and software in the network.

That is what I figured. I feel guilty but I think I will harvest the most beautiful 8-bit CPU ever made by Motorola (6809) from that card to play around for a single board computer. That card has all the necessary ICs for simple SBC, with 8kB SRAMs, 74 logic ICs, serial controller (Intel P8274) and RTC.

Can't see any ROM on that card though which begs the question where is the firmware stored? Maybe the PC loads the firmware on the seven 8kB sram chips (6264) on the fly?   

[Ian.M]

It would be nice if you can use it as-is as PC hosted 6809 development system, but then you have the aggro of figuring out its ISA bus interface, + finding and maintaining a PC with a slow enough ISA slot, but still with a recent enough processor to run a reasonably current OS to support available FOSS cross development toolchains.

Realistically, it makes more sense to gut it for the chipset and build your own board, possibly with a Pi Pico 2 (for the RP2350's 5V tolerant GPIOs and PIO engine) providing EPROM emulation and debug access via USB.

[m k]

So maybe a LAN/WAN link machine.

Can be either way, old 3270 controlled terminals to Token Ring "mainframe" or Token Ring LAN to remote old mainframe.

It's an era when IBM had field and enter keys.
3270 is a block terminal system.