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Discussion in 'Electronic Basics' started by Rich Grise, Aug 27, 2003.

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  1. Rich Grise

    Rich Grise Guest

    Hi. I just bought a new computer, and was thinking of ways to get all
    my stuff
    from the old computer to the new one. I thought, "serial link," which
    be fun anyway. So, since the local RS is in disarray during
    remodeling, I went
    to the local Home Club and got some 4-conductor, jacketed, shielded
    wire.So, OK, cool - I've got that stranded bare drain wire, which is
    frame ground,
    obviously, and a red, green, black, and white wire. So black or white
    be signal ground, and red/green RxD and TxD. So, what's the thing to
    do with
    the excess wire that makes the most sense? There _are_ four_
    handshake lines,
    if I want 1/4-duplex handshaking. If I did that, are there any ideas
    as to
    which particular wire (RTS -> CTS, DTR -> DSR, one way or the other)
    would do any good to connect? Or should I just tie it off.


    If you want to email me, elide 'ard'.
  2. You should make a null modem cable, but if you want it to work with most
    software you'll need 7 wires. Info here:
  3. The last time I did something like that I used something called
    generically a "Laplink cable" after the makers of an old program. and
    the INTERLNK.EXE and INTERSVR.EXE programs that were part of DOS.

    It works with two serial or two parallel ports, IIRC. I think I paid
    about $6 for the cable, which has two connectors on each end (a DB-9
    and a DB-25 of one sex or the tuther).

    Best regards,
    Spehro Pefhany
  4. Have you considerd moving the old hard drive into the new system
    temporarily? It is the easiest solution.

    Melvin Stevens
  5. John Jardine

    John Jardine Guest

    To transfer my old PC's hard disc contents (1 Gbyte) to this PC's hard disc
    I made up a "laplink" type cable that connects to both the LPT's. Data is
    transferred a nibble at a time and is fast. The Laplink wiring is standard
    and a number of web sites carry it. Total transfer time was something like
    an hour.
    Windows 95/98 carries the programme as something like ...
    "Start/Programmes/Accessories/Communications/Direct cable connection". Run
    this prog' on both PC's and copy the directories from drive to drive as if
    both PCs were just one PC.
  6. That pretty fast. I thought LPT traffic was limited to some 100K transfers
    per second, and being nibbles that would be some 50Kbyte per second or
    180Mbyte per hour.

    But who cares, it certainly beats using floppies ;)
  7. Dana Raymond

    Dana Raymond Guest

    I don't know if laplink uses them but all modern centronic printer ports
    support SPP, EPP, and EPT modes of operation. EPT can tranfer megabytes per
    second, assuming the rest of the system can handle it.

    Dana Frank Raymond
  8. There are other ways.. if it's got a modern O/S, drop a $10 network
    card into it.. or temporarily install a CD-RW drive.. or move the old
    HDD over to the new computer temporarily.

    If it's a laptop, the options are more limited, but there are
    inexpensive USB<->ethernet devices, and you can get inexpensive
    adapters to fit laptop 2.5" drives into desktop systems.

    Best regards,
    Spehro Pefhany
  9. John Jardine

    John Jardine Guest

    You're right!. Looking back I remember *not* transferring Doom and
    Wolfenstein. Must have saved me a couple of hours at least :).
  10. Don Kelly

    Don Kelly Guest

  11. You tie the DSR and DTR together (pins 8 and 20) on each end. Then you
    send the RTS on each end to the CTS of the opposite end. This is the
    standard null modem crossover cable. You can connect the shield on each
    end to both the shield pin 1 and sig ground pin 7, leaving all four
    insulated wires for signals.

    BTW, we will see you here some time late next week, after you get thru
    transferring all the stuff. Serial isn't fast enough fore today's data
    'aggregation'. You really need a Cat5 crossover cable for a pair of NICs.
  12. unix-freak

    unix-freak Guest

    If you have nics in each puter, then why not transfer files to the
    tune of millions of bytes per second as opposed to serial port's
    Just make or buy a crossover network cable.
  13. You will _not_ need 7 wires! For a null modem, using software
    handshake, AKA XON/XOFF, all you need is three, Txd, Rxd, and sig gnd.
    Or 5 wires for hardware handshake.

  14. It's the fastest but not the easiest. Most users haven't even got the
    knowledge to plug the ribbon cable in correctly, not to mention opening
    up the case (unless it's a Dell :p). The easiest is to get either a
    parallel port "Laplink" cable or a USB crossover cable and connect the
    two PCs together. If you have a USB 1.1, you will get about 100kB/s and
    a little bit faster with the parallel cable. If you have USB 2.0, it
    can be as fast as the hard disk, which might be in the 40 MB/s range.
    These are just rough estimates because of other variables such as
    processor speed, bus speeds, HDD speed, etc. It's easy to connect them
    with a Cat5 crossover cable, but not all PCs come with a NIC - newer
    ones have it built into the MoBo.

    But for backup purposes, everyone should already have some way of
    backing up the HDD, such as Ghost and an external HDD with USB 2.0. Or
    else be like the lady at our club, who has a sweatshirt that says:

  15. more like megabits per second. The slew rate of a parallel port is
    limited for some reason, might be for RFI or part 68 regulations.
  16. Andre

    Andre Guest

    1.40 UKP from Mr CPC :)
  17. Rich Grise

    Rich Grise Guest

    Thanks! :) That's a null modem, after all, which I found after a little
    research. The guy at the comp. place offered to sell me one for twenty
    bucks, but I'm a hacker. Connectors are about two bucks at RS, wire is
    free, and I already have a crimper.

    At first, I was going to move the drive, but I'm kinda reluctant to
    start messing with a brand spanking new system, and I've realized,
    hey, I've got two fully operational computers here! The new one has
    Win 2000, and the old one has Win 95 and Slackware Linux (one at a
    time, of course.) I also have a Motorola ICS05 in-circuit simulator,
    and at one point had the serial port going at 115000 bps or something

    In any case, connecting them together will be fun; I plan to try both
    windows networking file sharing, and set up the HTTP server (Apache) on
    the old box, and explore it with the new box via IE and DCC. (anybody
    ever heard of a wireless DSL link? Not a wireless LAN with a DSL box
    and wire, but a box that sends the DSL by RF, a la cell phone? Thanks!)

    Thanks, Everybody!

    Incidentally, I figured out why people are so prone to pop into the
    NG to ask a question when it's pretty clear that they haven't done
    much, if any, research - one, newbies don't know how, but more subtle,
    and possibly more important, is that after sitting at the computer all
    day, with our reference books and soldering iron and crap, staring at
    the same four walls, day in and day out, the NGs are the closest thing
    to human contact some of us make outside of the office! %-]

  18. Lord Garth

    Lord Garth Guest

    "...undemanding contact in your happy solitude." --- Geddy Lee (Spirit of
    the Radio, Rush)
  19. Jim Thompson

    Jim Thompson Guest

    On 28 Aug 2003 16:19:54 -0700, (Rich Grise)

    Absolutely! We need to have a reunion !-)

    ...Jim Thompson
  20. Don Bruder

    Don Bruder Guest

    Proper attribution and title: Neil Peart (The Spirit Of Radio)

    When it comes to Rush, even though Geddy does 99.9% of the vocals, the
    creative process is fairly "compartmentalized" - Neil writes the lyrics,
    and hands them off to Geddy. Geddy chases down Alex, and together, they
    write some music to go with 'em, then hand the whole thing back to Neil
    to see if he likes it. He tweaks a little here and there, figures out
    what the drum sound is going to be, they all get into the studio to work
    out any kinks, and next thing you know, there's another piece waiting to
    be heard by those who have enough taste to appreciate the very best,
    musically speaking.

    And yes, I'm a nit-picky Rush fan. So sue me :)
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