Retro Friday: Using (Almost) Any Computer As A Serial Terminal

A computer’s usefulness these days pretty much depends on whether it’s internet-capable or not. It doesn’t matter how the whatever-it-is connects to the internet be it by wired network, Wi-Fi, 3G or whatever is used so long as it can get there.

On the vintage computer side of things, the one thing just about any computer can do from the 1980s all the way up to now is act as a serial terminal.

The serial terminal experience

What you’re doing when dedicating a computer to serial terminal duties is that it’s basically no longer a computer at that point. All the true computing is done server-side, and the box you’re using is nothing more than an access point rather than something that can do things on its own.

What you can do via serial terminal connection is use anything text-based. A handful of apps you would use on a normal basis are:

Lynx, elinks or minicom (browsing)
Mutt, Pine (email)
irssi (for IRC)

What acts as the server?

Any computer you can get your hands on that can run Linux, connect to the internet and has a serial port your vintage computer can attach to via null modem cable.

How old can you go?

Very old.

One of the more popular means serial terminal’ing is with the Apple II using ADTPro. Grotesquely detailed instructions are here for that.

Here’s an example of it in action (if you want to skip to the part where it actually shows the computer doing its stuff, jump to 6:25 in the video):

[youtube https://www.youtube.com/watch?v=S4WHBQ7gmB4]

Where do I get instructions for setting up a Linux server to accept a connection from a serial terminal?

Everything you need to know is here:

http://www.vanemery.com/Linux/Serial/serial-console.html

Where do I get cables or cards?

If connecting IBM Compatible to IBM Compatible, cards like this one and cables like this one are readily available.

However..

Depending on what vintage box you’re trying to connect, you may literally have to create your own serial connector from scratch, or special-order one from others who make specialized vintage computer serial components.

Generally speaking, if the box is an IBM PC Compatible, it has a serial port that’s ready-to-use, even if it’s an IBM 5150 from 1981.

What software do I need on a DOS terminal?

For those that remember the BBS days, you’re basically doing the exact same thing you did back then, except you’re connecting locally instead of using a phone line.

On the terminal PC, you install the operating system MS-DOS or DR-DOS. If you don’t have a copy of that, don’t worry, there’s FreeDOS which will also work.

After that, you need terminal software.

Amazingly, ftp.simtel.net still has a whole bunch of DOS terminal software you can download and use in a DOS environment. Here are the addresses:

Some of the more popular terminal programs for DOS were Telix, Qmodem and Procomm – however don’t take that as gospel. Use whatever terminal app suits your taste.

ALSO REMEMBER: If your old box is running old Windows, Terminal and HyperTerminal will both connect over serial easily.

For example, if you have, say, an old Toshiba Satellite with Windows 95, that laptop has a serial port, and Win95 has HyperTerminal. If your Linux server is ready to accept serial connections, connect the null modem cable between the two machines and go for it.