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Connection Problems! — Parallax Forums

Connection Problems!

stedetrostedetro Posts: 3
edited 2005-06-21 21:52 in BASIC Stamp
Hello everyone,

I have a basic stamp2 homework board. It works fine on my laptop with a built-in serial port. But on my new laptop I am have no serial port, just USBs. I bought a Belkin USB to serial port adapter. The adapter works find with any other serial·device but does not work with the stamp2 homework board.

When I check Identify it says a BS2pe exists on COM2. When I go to download a program it fails with a "Hardware Communication Error!." I have tried switching ports, UART on/off, UART high speed/low speed and every other setting you could imagine.

I already have a running program from when I was using my other laptop. I see the red R light on the adapter going on and off as it should and when I goto the debug screen I see in3 = 0 as I should be.

Also when I hit a key in the debug window the TX light on my adapter goes on and off as it should so it seems like I am getting a connection both in and out.

I just don't get it. Any help would be appreciated.

Thanks,
Stede


Post Edited (stedetro) : 6/20/2005 1:46:08 AM GMT

Comments

  • Ken GraceyKen Gracey Posts: 7,400
    edited 2005-06-20 01:55
    Stede,

    The Belkin cable probably doesn't support the break condition in RS-232, so it will not work. There are many threads on this forum about serial to USB adapters. And this thread will probably quickly grow like the rest of them. Your problem could like with the hardware or drivers, but you'll never know for certain unless you put a scope on the serial output and compare the signals to the ones which are supposed to be present.

    Historically, people owning adapters have either decided to get one that works or to fight with the one they have already purchased. I suggest you take it back to where you bought it, and get one that works. For example:

    FTDI USB to Serial Adapter

    This one will work for certain with all of our products.

    RadioShack's USB to Serial adapter also works if you don't want to wait for ours. Theirs is $41.99 and available in most stores. Go to www.radioshack.com and check their inventory at a store near you.

    Ken Gracey
    Parallax, Inc.
  • stedetrostedetro Posts: 3
    edited 2005-06-20 02:01
    Well that stinks. I paid $50.00 for it a few months ago. They will not take it back. Is there anything, absolutely anything that could be done to get it to work?

    Is this a Windows problem or a Belkin problem?

    I guess even serial ports are not standard anymore. smile.gif

    thanks again,

    Stede
  • Jon WilliamsJon Williams Posts: 6,491
    edited 2005-06-20 02:14
    This is a Belkin *problem* -- though to them it isn't. Not all USB adapters support everything that can be done with a standard serial port, specifically the break condition that is required for BASIC Stamp programming. We did a lot of research to find and adapter and chipset that would work reliably; what we've settled on is FTDI -- it works, and we build it into our own USB-based products.

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    Jon Williams
    Applications Engineer, Parallax
  • stedetrostedetro Posts: 3
    edited 2005-06-20 02:20
    Then I guess I have to buy your USB adapter too. You guys are a pain smile.gif but your products are outstanding. I can't believe how much I am learning and how much fun it can be. Your service is also top notch! I appreciate your fast response.

    Thanks for your help,
    Stede
  • allanlane5allanlane5 Posts: 3,815
    edited 2005-06-20 12:31
    Sorry Stede, I've had problems with the Belkin adapters also. The best ones are the Keyspan 19, or the FTDI sold by Parallax. The problem you're running into is that some vendors (Belkin) take short cuts with the RS-232 specification -- and most USB adapters for PDA's also do not support the hand-shake lines properly.

    FTDI and Keyspan seem to have taken no short-cuts, and thus they are good replacements for a missing motherboard serial port. It's really not Parallax'es fault -- they can't control what other vendors do, and their use of the RS-232 port and handshake signals is completely standard.
  • RancheroManRancheroMan Posts: 14
    edited 2005-06-21 20:21
    This is the unit I use. I thought it was a good price.....





    http://www.hvwtech.com/pages/products_view.asp?ProductID=524
  • GadgetmanGadgetman Posts: 2,436
    edited 2005-06-21 21:52
    They state that it should work with the Basic Stamp, so...

    You may have another problem...
    Possibly the FIFO settings for the COM port?

    Check THIS thread.

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    Don't visit my new website...
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