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Raven
March 26th, 2010, 10:41 AM
The only external networking options for old computers I am aware of, barring the availability of PCMCIA in slightly less-old computers, are parallel and serial. Parallel port adapters include rj45, thinnet, thicknet, and various token ring adapters by Xircom. I haven't come across any serial port adapters to do the same thing (afaik there are only serial modems). Are there any? I also haven't come across any brands besides Xircom, and most of the Xircom cards are missing parts or selling for very high prices. I almost got one for $12 total - but someone outbid me at the last minute 'cuz I was too dumb to set a max bid. Anywho if anyone has any suggestions I'd like to find a way to hook my Panasonic Sr. Partner to the network without replacing the MFM controller I have in it's ISA slot, as that would force me to use external SCSI for storage, and that would be annoying in many ways due to the portable nature of the machine and it then taking up my parallel SCSI adapter.

Ideas?

Oh, and if anyone knows - without a doubt - about the second slot in the Sr. Partner, and whether it is usable for things besides RAM expansion, let me know.

Edit: Did find WIRELESS parallel adapters but I can't afford them - see http://www.vintage-computer.com/vcforum/showthread.php?19892-Found-these-WIRELESS-PARALLEL-adapters-on-eBay&p=133962#post133962 if you're interested.

MikeS
March 26th, 2010, 11:29 AM
There are RS-232<>Ethernet adapters but they tend to be expensive; sometimes you can find a Lantronix UDS-10 or similar on eBay for a good price.

There were (are) also RS-232<>RS-232 networks (LANtastic, etc.) that would let you network to a "server" via a serial connection and bridge to ethernet that way.

mbbrutman
March 26th, 2010, 01:46 PM
I would wait for a Xircom adapter .. these are the way to go. I have not had a single machine with a parallel port that a Xircom would not work on. They are portable and reasonably fast.

All of the higher speed stuff attaches to the parallel port and not the serial port for a reason - serial ports are just too slow. Before USB the parallel port was the general purpose way to attach devices externally, which is why there were so many parallel port attached CD-ROMs, hard drives, scanners, Zip drives, etc. A parallel port (depending on the type and CPU) can give you throughput in the 30KB/sec to 150+ KB/sec range, while a serial port will top out around 115,000bps, which should be 20% lower because of the overhead of stop and start bits.

If you want network connectivity and all you have is a serial port available, you have a few choices:


Use your machine as a terminal to a more capable machine, like a Linux box. This requires a null-modem connection.
Run SLIP/PPP over a null modem connection to a Linux box. You will be running TCP/IP right on your old machine, which will require more memory than just using your machine as a terminal, but you get the satisfaction of running the apps directly on the machine.
Use a Laplink style cable and run SLIP/PPP over the parallel port instead. Same as option two, but faster because the parallel port has much better speeds.


All of these options require another machine to serve as a gateway between your old machine with the serial or parallel port and the outside world.

Raven
March 26th, 2010, 02:23 PM
I have used it as a terminal before, but that feels like cheating to me, unless I could find an old-fashioned mainframe or something more legitimate to connect to. I actually bought a Xircom, but it had no power adapter, and the douches at Radioshack told me that "it doesn't matter what polarity you use" and had me fry it right in their store - bastards. Most of the ones on eBay go for a lot these days, $30-50... Anybody have one they'd sell for more like $15, preferably with the ps/2 leech power connector?

I'm aware that serial is slower, but I'm trying to hook an 8086 to my network primarily for file transfer, so speed isn't too important or anything. I might use it for IRC chatting, but nothing too intensive. It does make sense that there aren't many adapters though. The machine does have parallel, anywho.

glitch
March 26th, 2010, 02:40 PM
If you've got a free ISA slot, there are lots of Ethernet adapters that are either 8-bit or will work in an 8-bit compatibility mode.

Ole Juul
March 26th, 2010, 03:00 PM
If you've got a free ISA slot, there are lots of Ethernet adapters that are either 8-bit or will work in an 8-bit compatibility mode.

He didn't want to use an ISA slot. :) Anyhoo, I'm with Mike in that SLIP/PP is the way to go for real networking. Laplink/interlnk is probably the simplest way to go for file transfer and it's pretty fast too. If you're willing to run MS-DOS 6.x, interlnk/intersvr requires only one small executable on each machine.

Raven
March 26th, 2010, 09:54 PM
I'm already running 6.22 on my Sr. Partner as I found no real reason to run the original 2.11 over it other than authenticity, and since it had no HDD when I got it I wasn't wiping anything out and still have the disks. I've tried to get that working before to no avail - perhaps I'll try again - I assume that that isn't a possible way to get internet access on a box though?

Ole Juul
March 26th, 2010, 11:55 PM
I'm already running 6.22 on my Sr. Partner as I found no real reason to run the original 2.11 over it other than authenticity, and since it had no HDD when I got it I wasn't wiping anything out and still have the disks. I've tried to get that working before to no avail - perhaps I'll try again - ...

Interlnk is pretty foolproof if you got the right cable - do you? They used to sell them, but the diagram is right in the MS help files. ("help interlnk" under notes.) Software wise, the important information is that interlnk.exe goes on the client and has to go in the config.sys file. That part is easy to miss. :) You can't start the client (interlnk) after you've booted, although you can start and stop it once it's in memory. The server part just goes in the autoexec.bat or type "intersvr" on the command line. There's not much else that can go wrong except if you don't have drive letters enough. Put "lastdrive=Z" in your config.sys and you're good to go. Other things that can be configured or played with won't effect basic functionality. Once you're up and running you can type "interlnk" to remind you of what the drive letters are.

To sum up:
interlnk goes in the config.sys
intersvr goes in autoexec.bat or just type it
put "lastdrive=Z" in your config.sys


I assume that that isn't a possible way to get internet access on a box though?
No, interlnk is just for moving files back and fort or reading them. I love it, and always have a second DOS machine connected to my main one. It gives me more drive space and access to two more floppy drives. BTW, both my internet and interlnk are always running. Those are basically unrelated.

However, when it comes to SLIP/PPP then that is real networking and you can connect to the internet directly through an ISP dialup account or another local machine which is connected in any way.

Raven
March 27th, 2010, 07:59 AM
What is required to set up SLIP or PPP hardware wise? I've got parallel and serial ports, null modem cables and null modem adapters, and even a nifty null modem cable that has parallel and serial ports on both ends that you can choose from - is this enough to set it up with another machine? What does the host machine need to have? I tried to set this up once and couldn't get the Sr. Partner to dial into a modern NT box with the "advanced" direct cable connection setup.. Was I going about this wrong? Is there a tutorial or FAQ?

Thanks for all this info, btw.

Maniak
April 1st, 2010, 08:21 AM
If your just looking for a way to "network" the computers together through DOS (no tcp/ip), LANtastic Z was a 2 computer network for Dos based machines. It ran on Serial cables (same as a laplink cable).. The trick will be finding LANtastic Z software. You can then share drives and printers between the 2 boxes.

MikeS
April 1st, 2010, 01:55 PM
If your just looking for a way to "network" the computers together through DOS (no tcp/ip), LANtastic Z was a 2 computer network for Dos based machines. It ran on Serial cables (same as a laplink cable).. The trick will be finding LANtastic Z software. You can then share drives and printers between the 2 boxes.Couldn't you daisychain to more than 2 computers?
And there were other similar RS-232 network packages as well; Also-LAN (by a local company) springs to mind.
And of course there were also the remote control packages like Carbon Copy, PCanywhere, etc.

Ole Juul
April 1st, 2010, 08:53 PM
What is required to set up SLIP or PPP hardware wise? I've got parallel and serial ports, null modem cables and null modem adapters, and even a nifty null modem cable that has parallel and serial ports on both ends that you can choose from - is this enough to set it up with another machine? What does the host machine need to have? I tried to set this up once and couldn't get the Sr. Partner to dial into a modern NT box with the "advanced" direct cable connection setup.. Was I going about this wrong? Is there a tutorial or FAQ?

Thanks for all this info, btw.

In the parallel thread (http://www.vintage-computer.com/vcforum/showthread.php?19865-Serial-Modem-Emulator) to this I gave details after setting it up myself.

I didn't get what operating system you were using on the client. I used DOS on the client and Linux on the server. To network over a serial line you only need a null modem cable, and EPPPD on each of the machines. After playing with it for a couple of days, I still can't believe how simple it is.

Just to sum up, you put EPPPD.EXE (45K) on the DOS machine and simply type the name (with arguments) or put it in a batch file. On the Linux box you will have PPP functionality built in so you just type "pppd" (with arguments) on the command line. Don't forget to turn on port forwarding if you want your DOS box connected to points beyond your lan. (ie. the internet) The "e" in epppd on the DOS box is just to denote a version that emulates "e"thernet. That way one can use regular ethernet programs and they will think they are talking to an ethernet card when they are really being put through a serial port.

I'll help you with the nitty gritty if you like, but I have almost no knowledge about Windows. However, I can't see the setup on NT being significantly different from Linux. It just needs a PPP server. ISPs have been using PPP and offering dialup for years and surely some of them have used NT. Certainly, leaving the modems out of it makes it really simple.

Chuck(G)
April 1st, 2010, 09:25 PM
Before I used a regular NIC to network, I used a package called "The $25 Network" (http://www.funkymonkey.ie/file-archive.html?func=startdown&id=117) that went serial-to-serial and worked very well. Mutliple systems could be hooked together if each system had at least 2 serial ports.

There were a number of competitors using NICs of one flavor or another. Banyan Vines, ARCnet, Invisible Network, TOPS, etc.

I believe that Novell got its start using serial RS-422 multi-drop networking. With a RS-232-to-RS-422 converter, it still might be an option.

Quite a number of inexpensive microcontrollers have CAN networking facilities. It wouldn't be hard to devlelop a CAN-network board with a uC that interfaced to RS-232 or parallel ports.

MikeS
April 1st, 2010, 09:45 PM
Before I used a regular NIC to network, I used a package called "The $25 Network" (http://www.funkymonkey.ie/file-archive.html?func=startdown&id=117) that went serial-to-serial and worked very well. Mutliple systems could be hooked together if each system had at least 2 serial ports.Same here, although the package I used was called AlsoLAN; DB25<>RJ45 adapters and phone cable daisy-chaining from one system to the next, and line drivers for long and/or noisy runs. Still a viable option today for my older laptops without ethernet or USB ports, and I use PCanywhere/DOS for remote access over POTS several times a day; just like a multiport KVM with very long cables ;-)