Dumb user needs dumb terminal - Ubuntu

This is a discussion on Dumb user needs dumb terminal - Ubuntu ; I need a solution that will give me a dumb terminal to a PLC via a serial cable, and I need it asap. The PLC runs a heating system [ground source heat pump] in a house in Maine that I ...

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Thread: Dumb user needs dumb terminal

  1. Dumb user needs dumb terminal

    I need a solution that will give me a dumb terminal to a PLC via a serial
    cable, and I need it asap. The PLC runs a heating system [ground source
    heat pump] in a house in Maine that I would like to leave alone for the
    winter, and before the snowbanks get high. The system is largely
    redundantly controlled by analog controllers and will not fail
    catastrophically under normal circumstances. In an ice storm with
    multiple or extended power failures, recovery is much more difficult. The
    box I was using intermittently for a programming terminal is an [_very_]
    old one, running MS DOS 6.22 and telix 3.51, is having [probably terminal]
    hard drive issues. It has I/O of keyboard and display, serial port and
    3-1/2" floppy, period. I downloaded a new copy of telix and tried to run
    it from floppy and got an error:

    FATAL ERROR: No language file found ! TELIX aborted.

    I Googled that and found no solution.

    I have 4 other (old) 'working' boxes here, some dual boot [M$ & *nix],
    each with various issues and standard serial port connectors, and one new
    Dell Inspiron 1420 notebook running Ubuntu 7.04, which has only USB I/O,
    full networking and DVD RW. No 3-1/2" drive. Have been using a USB flash
    drive to move stuff between these systems. I now have 4 boxen running
    here that barely talk to each other with great effort on my part, and none
    so far that will talk to the PLC.

    I ordered a serial to USB connector [USB to DB9 Serial Port Adapter Cable]
    from http://www.emtcompany.com/index.html, which won't be here for another
    week at best. With the holiday, it will probably be the end of November.
    Happy Thanksgiving to all. I didn't want to wait that long. But the issue
    is not really the connectors. The issue to me now, even if I get
    connected, is how to get the dumb terminal set up.

    I know that to some smart administrators this would be a simple issue to
    resolve. But I am just a dumb user in search of a dumb terminal to adjust
    a PLC running a very clever [if I say so myself] heating system. I have
    Googled for directions and instructions and HOWTO's for setting a serial
    dumb terminal, and searched tldp.org. But there is just so much there
    that I cannot find the stuff I need to know, even once I can get
    connected. I downloaded minicom and read all that. And it is much more
    than I need to know, and not enough to accomplish what I need to do.
    Obviously, I would rather do this under Ubuntu or some other Linux, but I
    am not picky and will use what I need to so long as I don't need to buy a
    new computer or install a new OS. My latest M$ OS is Win98SE; all those
    systems have issues and all the disks are in the bottom of corrugated
    cartons. What I have is what I have and I need to make it work. Assuming
    that I could find the correct device or port, how would I do that, and how
    would I set a simple terminal to talk from my keyboard to the serial PLC
    and back to my display, please? Please folks, I need a helping hand here.

    And thanks.

    Pointers and links appreciated.

  2. Re: Dumb user needs dumb terminal

    oOg wrote:

    If running linux I would think minicom is all you need and I would hope it
    is included, or available as a package for, all distrubutions, whether on
    installed to hard drive or live cd/dvd or memorystick.

    As you say, locating the serial port if the main issue, try looking
    for /dev/ttyS*, usb to serial convertors may lie around /dev/usb somewhere.

    One thing to watch, one of my usb to serial convertors does not seem to have
    its ground pin connected, only tx and rx which caused me a great amount of
    fun with a development board, they would only talk when the dev board was
    earthedd via an oscilloscope probe.

    If the heating system if of your own design might be worth looking at one of
    the FDTI chip modules or leads so you can easily convert it to USB to make
    it more modern pc friendly.

    > And thanks.
    > Pointers and links appreciated.


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