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Sending a copy of LapLink over Serial

3lectr1c

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Hello. I've heard in the past that you can use LapLink on one computer to send a copy of LapLink to another computer using MODE.COM over serial. I have a host computer with LapLink for Windows 95 installed (IBM ThinkPad 385XD), and a target computer (Toshiba Tecra 500CDT) that I currently have no way of getting files onto. The internal CD-ROM drive isn't recognized by Windows and it has no floppy drive. Also, like all my other Windows 9x laptops, it refuses to mount a CF card in a PCMCIA adapter (really really wish I could get that figured out!). It has Windows 95 installed though, and I've got a Null modem serial cable.

So the issue is: I can't find the option anywhere in the software to send a copy of LapLink over. How would I do this? Thanks!
 
Windows 95 has “direct cable connection” if it was installed. If it’s not installed you’d need to install it. Maybe you’re lucky and someone copied the CAB files to the HDD at some point.
 
INTERLNK was my first thought too but it appears the Tecra doesn't have it. I also did try DCC but it didn't work either, the computers couldn't find each other. And yes I'm using the right type of cable, I tried a LapLink parallel cable and a null modem serial cable.
 
INTERLNK has an option /RCOPY: "Used to copy Interlink files from one computer to another, when the computers are connected with a 7-wire, null-modem serial cable and the MODE command is available on the computer on which you are installing Interlink" (source). Perhaps that would work?
 
Could try that, yeah. Thanks!

Right now I've made some progress with DCC on Windows, but it still won't work. It now detects something, but instantly throws a message up that "Parallel cable on LPT1 disconnected". That's better than before where it would just sit there looking, but still obviously that means it doesn't work.
 
Ughhhh. This is all just so incredibly infuriating. I have all these cables, all these laptops, running all these operating systems, and all these tools that I should be able to use to get files over to pre-USB laptops and yet NOTHING works. NOTHING!

- I try Windows Direct Cable Connection and it won't connect no matter what I do. I followed online tutorials exactly to the letter but it just doesn't work.
- I try the INTERSVR /RCOPY method and the Tecra just locks up after I type the second command it instructs me to type
- I try a PCMCIA CF card which ABSOLUTELY SHOULD WORK on Windows 9x and it DOESN'T WORK on ANY of my laptops with Windows 9x. NONE OF THEM! And no one here seems to know how to fix it either!
- Oh and then of course there's the Tecra's CD-ROM drive. It's detected in the BIOS. I can open the disc tray. When I insert a disc, it spins it up and sounds as healthy as can be. But Windows and DOS both act like it isn't there. Why? Who knows! If it worked then I could burn interlnk or LapLink or whatever other tool to a disc and do things that way. But nope.

I feel like the only thing I have left to try is to try and track down an older version of laplink that can transfer itself over MODE? But I feel like that isn't going to work either because I just tried basically the same thing using INTERSVR and it didn't work there. I'm sick and tired of dealing with this and feel ready to just give up out of frustration with this thing. I've given up troubleshooting dead computers before but it takes a LOT to get me to give up out of frustration alone. I just don't get why this all has to be so darn difficult. It should be simple. It would be simple if what people said should work actually worked. But it never has for me, I've been dealing with these same issues across multiple laptops for months.
 
I know the feeling...

- I try Windows Direct Cable Connection and it won't connect no matter what I do. I followed online tutorials exactly to the letter but it just doesn't work.
but instantly throws a message up that "Parallel cable on LPT1 disconnected".

There's something strange. On the opening post you mention "A null-modem serial cable". That won't be LPT1 (parallel port) so DCC will surely fail if it attempts to listen on LPT1 instead of serial ports?

Are you also sure how the serial ports are numbered? I noticed that both machines (at least should have the option) for IrDa (infrared) ports, and I believe that in some of my older Thinkpads that was COM1 and the actual serial port was COM2 (this took my way too long to notice). How many ports you see in Window's Device manager?

Btw; you could even attempt to use the infrared ports (if both machines have them); I hadn't even thought of that until I just saw this:

- I try the INTERSVR /RCOPY method and the Tecra just locks up after I type the second command it instructs me to type

Yeah the commands will basically turn keyboard input to the serial port and the machine will appear locked up (until the transfer would release it at the end).

- I try a PCMCIA CF card which ABSOLUTELY SHOULD WORK on Windows 9x and it DOESN'T WORK on ANY of my laptops with Windows 9x. NONE OF THEM! And no one here seems to know how to fix it either!

A long shot; but what format is the CF card using? If it's FAT32, that won't work (unless you have Win95B/the latest rev that also included rudimentary USB support). Although I'd guess Windows should notice a new disk drive anyway (unless there was a problem with the PCMCIA slot drivers - are there any exclamantion point'd devices in the Device manager?).

- Oh and then of course there's the Tecra's CD-ROM drive. It's detected in the BIOS. I can open the disc tray. When I insert a disc, it spins it up and sounds as healthy as can be. But Windows and DOS both act like it isn't there. Why? Who knows! If it worked then I could burn interlnk or LapLink or whatever other tool to a disc and do things that way. But nope.

There's also a chance that the drive wouldn't read CD-R/RW's anyway ;)
 
On DCC - I’ve tried both a LapLink parallel cable and a null modem serial cable. With the serial cable, the computers never detect each other at all… with the parallel they do as mentioned. And yeah they have COM1 and COM2 and I figured one may be infrared so I tried both. No change.

On INTERSVR - how long would this take? Because I left it for a couple minutes and the interlink files are tiny. Also did respond to control alt delete during this time

On CF - tried seven laptops running 95 OSR 2.5, 98, Me even and all don’t work. Cards formatted as FAT anyway. Adapter and cards work fine on XP and in Mac OS.

Thanks for your help. It’s possible my serial cable is junk or something, but I bought it as a null modem cable…
 
Ughhhh. This is all just so incredibly infuriating. I have all these cables, all these laptops, running all these operating systems, and all these tools that I should be able to use to get files over to pre-USB laptops and yet NOTHING works. NOTHING!
I think you are doing something wrong. Serial cables have never failed me, as long as the wiring is correct.

- I try Windows Direct Cable Connection and it won't connect no matter what I do. I followed online tutorials exactly to the letter but it just doesn't work.
One step before the other. Do you actually know that your serial connection works? Don't try fifteen tutorials with twelve cable variants and twenty machines until you know what you are actually trying to do.

- I try the INTERSVR /RCOPY method and the Tecra just locks up after I type the second command it instructs me to type
Yes, this is correct. If you open a terminal program on the connected machine and configure it accordingly ("MODE COM1:2400,N,8,1" means 2400 bps, 8 data bits, 1 stop bit, no parity; "CTTY COM1" means "switch keyboard/screen to COM1"), you should see the DOS prompt on the other machine and be able to use DOS remotely. Also, stuff like "echo abc > COM1" must work correctly.

If that does not work, you have a wiring problem, a hardware problem, or used the wrong port. Your serial cable must be a null modem cable, not a random serial cable. I am not 100% sure whether the hardware handshaking lines must be wired correctly, or whether you can get away with a three-wire interface.

- I try a PCMCIA CF card which ABSOLUTELY SHOULD WORK on Windows 9x and it DOESN'T WORK on ANY of my laptops with Windows 9x. NONE OF THEM! And no one here seems to know how to fix it either!
I replied in your other thread that I think your cards are too big. And at least I only check a few forums and not too regularly.

- Oh and then of course there's the Tecra's CD-ROM drive. It's detected in the BIOS. I can open the disc tray. When I insert a disc, it spins it up and sounds as healthy as can be. But Windows and DOS both act like it isn't there. Why? Who knows! If it worked then I could burn interlnk or LapLink or whatever other tool to a disc and do things that way. But nope.
Well, both Windows and DOS need drivers for the drive to work. For IDE drives, I have used OAKCDROM.SYS from Windows 98 with a very high degree of success (and MSCDEX, of course). Windows 95 (the original version) also had a fun issue where it wouldn't install its own drivers and lose its own installation CD during the installation. Fixed by making sure that the DOS driver works.

I feel like the only thing I have left to try is to try and track down an older version of laplink that can transfer itself over MODE?
Norton Commander 5 can also remote-copy itself over a serial link, similar to INTERSVR. I even had moderate success running the host-side inside DOSBox using a USB-to-serial adapter, but it wasn't too reliable. So use a DOS machine on the other end.

You mentioned lots of laptops. Use one to talk to the other. Make sure communication works.

On DCC - I’ve tried both a LapLink parallel cable and a null modem serial cable. With the serial cable, the computers never detect each other at all… with the parallel they do as mentioned. And yeah they have COM1 and COM2 and I figured one may be infrared so I tried both. No change.
For serial cabling, use a terminal program to verify communication and cabling. Norton Commander comes with TERM95, which is acceptable. CTTY works in a pinch.

On INTERSVR - how long would this take? Because I left it for a couple minutes and the interlink files are tiny. Also did respond to control alt delete during this time
The serial communication process is very slow. Transmissions at 1200 bps are just barely faster than my reading speed. This is done for reliability, because you cannot use a checksumming protocol until you have both sides working correctly. Communication will speed up substantially when things work, but it will be slow. (For comparison, serial communication is limited to either 19.2 kBps or 115.2 kBps depending on driver/interface, and your floppy drives run at 250 or 500 kBps).

On CF - tried seven laptops running 95 OSR 2.5, 98, Me even and all don’t work. Cards formatted as FAT anyway. Adapter and cards work fine on XP and in Mac OS.
The PCMCIA drivers for mass storage are designed for 2 MB SRAM cards. They were never designed for CF cards a thousand times larger.

Thanks for your help. It’s possible my serial cable is junk or something, but I bought it as a null modem cable…
Measure the wiring.
 
Thanks for the help. Do you have a tutorial on how to properly check the wiring of the cable? It was definitely advertised as a null modem cable when I bought it.
And I’ll check out Norton commander - thanks!
Right now I think I’ll try RCOPY again and leave it for longer, just to make sure.
 
Use a multi-meter and check which pins go where. If you search for "null modem cable pinout" you find wiring diagrams, but they are also included with the documentation of LapLink or similar software. Wikipedia has an article as well: https://en.wikipedia.org/wiki/Null_modem

Unfortunately, the first stage of remote copying (which you are having trouble with) cannot have any form of progress indicator. So use a terminal program to make sure communication works. Both Windows 3.1 ("Terminal") and Windows 95 ("HyperTerminal") contain decent tools for the remote end. Also, you may try to connect two machines which you know are good.

You must be able to type messages from one machine to the other first. Otherwise, nothing will ever work and you are just wasting your time.
 
A key sentence from that is, "Several wiring layouts are in use because the null modem connection is not covered by the RS-232 standard." In the 80's and 90's, I worked in areas that used serial connections extensively. It wasn't a case of having two null-modem cables (one for DTE-to-DTE and one for DCE-to-DCE) with only those two cables catering for every situation that required a null-modem cable. There were situations that required that a specific wiring of null-modem cable be constructed.

Null-modem cable is a class of differently wired cables.

The null-modem cable wiring required by Laplink (same cable for INTERSVR/INTERLNK and FastLynx 3.3) can be found on the internet.

Some Laplink information is at [here].
 
Man this is complex. Maybe it would be easier at this point to figure out why DCC won’t work over parallel. I know that cable is good because I’ve used it with INTERLNK before. Any ideas why it instantly disconnects?
 
Man this is complex.
The 'null-modem' cable that was advertised at my local electronics store turned out to be the one required by Laplink (and INTERSVR/INTERLNK and FastLynx 3.3)

Note that the use of a USB-to-serial adapter can sometimes introduce a problem. For example, the one I picture at [here] works when I use it for a serial drive connection, but does not work when I try to use it for transferring its DOS slave program of FastLynx 3.3
 
Well I bought mine off eBay who knows what it really is. It does feel pretty cheap.
 
Do you have any idea why DCC over parallel instantly disconnects?
 
9448CB93-DCD4-4085-88C8-A9215B901042.jpegAs if it couldn’t be even worse as well, I can’t even get the hard drive out to transfer files to it that way. Service manual says I pull up on the metal handle and it should pop loose, it bent out of shape instead and won’t budge. Ughhhhh.

Edit: nevermind, there was a plastic bit I had to remove.
 
Ok, got a solution for now. Used an IDE to USB adapter to get LapLink on the Tecra, and now it’s happily syncing up with my ThinkPad. Sucks that I can’t seem to get PCMCIA to work, but this will do. The ThinkPad has USB, so it can be a bridge machine.
0D7B06C5-3AB8-4BD6-8326-A11F0F00655D.jpeg
 
The advantage of serial cables is that they are easily tested using off-the-shelf terminal programs, which often also can transmit files (xmodem, kermit) through the most basic of cables (three wires only). Parallel cables are much harder to test without software, and you may have to deal with SPP / EPP / ECP type parallel port differences. I've never bothered and always opt for serial or Ethernet.
 
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