Connect with us

Input Board

Discussion in 'Electronic Basics' started by Seb Schöps, Jan 6, 2004.

Scroll to continue with content
  1. Seb Schöps

    Seb Schöps Guest

    Hi everybody,

    I am looking for a board that can read the conditions of about 100 switches
    and transmit them to the PC. I found something here:
    http://www.alfasprint.be/InputBoard.htm
    The board has 32 inputs, but the thing is that it costs 100 Euros (about 125
    US-$) a piece.
    Is this price too high - what do you think? Or do you know alternatives?

    Any help appreciated!

    Regards Seb
     
  2. Bob Masta

    Bob Masta Guest

    If you don't mind building a little circuitry, how about the
    printer port? You can read 5 bits at a time from the
    status port, and use the data port to select a multiplexer
    channel. This will allow up to 256 x 5 channels. Or you
    can use bidirectional mode and read 8 data bits at a time
    from the data port, with a pin from the control port to
    latch the multiplexer.

    This will work with simple I/O commands on Win9x or
    earlier systems, but may need a special driver for
    NT/2K/XP systems.


    Bob Masta
    dqatechATdaqartaDOTcom

    D A Q A R T A
    Data AcQuisition And Real-Time Analysis
    www.daqarta.com
     
  3. CFoley1064

    CFoley1064 Guest

    Hi everybody,
    Hi, Seb. First, if you are considering just interfacing with switches, have
    you looked at using a switch matrix? You can read up to 100 switches with a 10
    X 10 switch matrix, which will limit your I/O requirements to 10 input lines
    and 10 output lines. You will need some diodes and pullup resistors (you
    should use Schottky diodes to minimize voltage drop, especially if you have any
    distance between the switches and the PC) as well as a circuit board or
    perfboard to mount the components and provide termination for the switch wires.
    The software overhead for reading a switch matrix is minimal.

    The page you specified reads like the module has optoisolation of the inputs,
    as well as built-in terminal blocks. For the price, it seems like a very good
    value, but I'm not sure you really need 3 or 4 of these just to read 100
    switches.

    Good luck
    Chris
     
  4. Chon Tang

    Chon Tang Guest

    Seb,

    Looking at the option that you looked at, I'm still not particular
    clear how you ultimately interface the board..? It mentions
    synchronous serial and parallel, I'm not sure if that's enough
    information for you to get started with.

    I wanted to recommend something that our company provides:
    http://www.tern.com/rengine.htm
    http://www.tern.com/p100.htm

    The R-Engine is the core, C/C++ programmable controller. x86-based,
    clocked at up to 80 Mhz, it supports 3 RS-232 ports, up to 32 I/O
    pins, etc. The P100 can then provide an additional 96 programmable
    I/Os. Total price for the system: about $198.

    The board's certainly more powerful as well. With a full 1 MB of
    memory space and fully C-programmable, you can implement a wide range
    of additional embedded control behavior. The interface to the PC
    would be straight-forward: you can set up a serial port connection
    with your PC's com port, and control the board through a simple
    terminal.

    I'm going to keep it relatively short here. If you have any interest
    or questions at all, do drop me an email at the address above!
     
  5. the Wiz

    the Wiz Guest

    Boondog www.boondog.com has a 24 port board (based on the 8255 chip) for $69
    assembled and tested. Don't know how many you can put in the same PC.

    More about me: http://www.jecarter.com/
    VB3/VB6/C/PowerBasic source code: http://www.jecarter.com/programs.html
    Freeware for the Palm with NS Basic source code: http://nsb.jecarter.com
    Drivers for Pablo graphics tablet and JamCam cameras: http://home.earthlink.net/~mwbt/
    johnecarter [email protected] mindspring dot.dot com. Fix the obvious to reply by email.
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-