View Full Version : HOWTO: Networking your XT/AT to a modern(ish) network

July 19th, 2014, 05:06 PM
Mods: If you think this should be in another section feel free to move it - I am just guessing this section is most appropriate.

For reference sake I would like to share my experience in networking my old XT's and AT's to a modern LAN.

I'm sure everyone here knows the pain of having to use floppy disks to transfer data. The limited capacity, scant reliability and slow transfer rate usually adds up to spending more time installing a piece of software than enjoying it. As such it is quite desirable to network your old PC's so that you can copy files quickly and error-free!

What you will need:

PC XT/AT with a free expansion slot
Suitable 'old' network card. If you have a COAX network then any old COAX card is fine. If you want to connect to RJ45 then you need something that has a DB15 port on the back. I use a WD8003E which is actually a rebadged SMC Ethercard Plus. An NE2000 will also work fine. For a full list of supported cards have a look at the LANMAN documentation.
A DB15 to RJ45 transceiver (if connecting to an RJ45 network).
Microsoft LANMAN software (available free off many places on the web).
MSDOS 3.3 (may work on older versions; but I tested on 3.3).
Old Windows 95/98 machine to connect to. This is by far the easiest thing to connect to; newer OS's have different security protocols which inhibit connectivity.


Microsoft LANMAN can only connect to shares; you cannot share your local drives.
DHCP is supported; however I could never connect to the server. This is probably because it's embedded into a modem. Recommend using static IP's.
LANMAN is quite large and will take up a bit of hard disk space (around 5MB if memory serves).
LANMAN takes up a lot of memory - but this can be mitigated (see below).

Since we are all quite familiar with the basics I will keep this brief. Here's what to do:

Get LANMAN onto your PC whichever way you know how. I used FX and a parallel port transfer as LANMAN is about 5MB is size. Unzip LANMAN into a single directory (don't forget the /d option as it unzips into subdirectories).
Backup your config.sys and autoexec.bat. You will need these to effectively disable LANMAN at times due to its memory useage.
Install LANMAN and follow the prompts. Everything is quite self explanatory. Remember you will need to know the IRQ etc of the network adaptor. As noted above I used static IP's as DHCP would not work. Make sure your workgroup is the same as your win98 box.
Edit the config files as LANMAN suggests; basically this just checks the IRQ of the network adaptor.
Reboot and log in using some valid credentials for your windows 98 shares. Don't worry if it says it cannot find a server to connect to.
Try 'net use X: \\myserver\share' which will effectively map your share to the X drive (obviously replace X and myserver\share to your applicable circumstances).
Enjoy the reliability.

Some things to consider:

As I noted above LANMAN uses a lot of memory. I have two sets of config.sys and autoexec.bat files. One is bare bones and the other starts the LAN. I only use the lan configuration when copying files; otherwise I use the bare bones ones to run the actual programs. To simplify this process I have a simple batch file which automatically switches between them.
The networking wont be blisteringly fast; it's actually quite slow. Its very reliable though!
You can try to load the LANMAN drivers into high memory; but in Dos 3.3 this WILL NOT WORK. They do actually load into highmem without errors; but later on it tries to load the client which cannot find the drivers. I suspect this will work ok in later versions of DOS.

Hope this is useful to someone. The hardest part is finding the old network cards - the RJ45 transceivers are common as dirt!

July 19th, 2014, 05:32 PM
I think this is an appropriate section. If the thread does not get too polluted it we could probably make it "sticky" so that it doesn't disappear into history too soon.

Your howto is centered around MS LANMAN, which provides a network drive letter. I think you point out the two big limitations; RAM usage and disk space required.

If you just want occasional file transfers you don't need the bloat of MS LANMAN - FTP is a good alternative. You can load a packet driver in just a few kilobytes of memory and run the FTP program when needed; all of it runs fine on a 256KB system. Packet drivers are small enough where you can leave them loaded in memory and not worry about the space utilization. (And many packet drivers support the "-u" option to unload them if you do need to reclaim the memory.)

mTCP (my set of DOS TCP/IP programs) is one place to start: http://www.brutman.com/mTCP .

If anybody has a howto style document for Novell type networks that would be good to add to this thread too.


July 19th, 2014, 05:46 PM
For bridging thinnet and ethernet segments I use a hub with bnc connector.

July 19th, 2014, 06:04 PM
The DHCP issues are probably because newer DHCP servers send extra information that confuses some older clients. I had a similar issue with the QNX 1.44mb floppy disk. If you need DHCP, you might try this simple Win32 DHCP server: http://www.dhcpserver.de/dhcpsrv.htm that worked for QNX.

July 19th, 2014, 06:14 PM
If you want to connect to RJ45 then you need something that has a DB15 port on the back.

Eh? I use Artisoft AE2/T cards and don't have a DA15 (that's the correct term) on it. Just an RJ45 jack. I suspect that a fair number 16-bit cards are also capable of operation in 8 bit slots as well. NE-1000/2000 cards seem to offer the fewest headaches.

You can interface with any "modern" OS if it supports an ftp host. It's just not Microsoft networking.

July 19th, 2014, 10:53 PM
This might be better as a locked sticky linking to a wiki - there's lots of potential info around this subject that could use some structure.

Using NetBEUI instead of TCP makes for a smaller memory footprint, if sticking with Microsoft networking stack. Windows NT, 2000, or Server 2003 (including the WHS derivative) can be used directly by DOS LANMAN clients without a fuss.

Another option is to boot the machine itself over the network using ATAoE or a derivative - actually Mike Chambers (IIRC) wrote a client/server combo to do just that already.