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Hyperterm and USB to serial adapter? — Parallax Forums

Hyperterm and USB to serial adapter?

wolffwolff Posts: 43
edited 2005-10-25 13:37 in BASIC Stamp
I just bought a new laptop and it does not come with a serial port (DB-9). So I purchased a USB/Serial port (DB-9) adapter from Parillax. I can program/run/debug my BS2 through the adapter with no problem... But when I try to use Hyperterminal to read a simple 9600 baud 8N1 stream it will only show about 50 charicters then stop. If I disconnect then reconect (using the software buttons on hyperterm) I get about 50 more characters then nothing?
Any help would be most appreciated!!!!

Comments

  • PJAllenPJAllen Banned Posts: 5,065
    edited 2005-10-23 01:56
    Just a suggestion --·perhaps look into the "Receive Buffer" setting (Control Panel/System/...)
  • wolffwolff Posts: 43
    edited 2005-10-23 20:35
    There is not a Receive Buffer setting. There are a bunch of other thing I have tried to tweek but nothing has any effect? Any one else want to weigh in?
  • allanlane5allanlane5 Posts: 3,815
    edited 2005-10-24 14:33
    When you close and re-open the serial port from hyperterm, it resets your BS2.

    It sounds like your BS2 program has a problem, that after 50 characters it 'locks up'. You'll have to look into that. If you get any characters at all from the BS2, the hyperterm -- USB -- Serial -- BS2 communication path is working fine.

    Oh, and by "locks up" I mean your code goes into an infinite loop, or enters a DEBUGIN statement, or enters a SERIN statement and waits for input forever, or possibly your battery goes low and does a 'brown-out' of your BS2.

    I certainly don't mean there's anything wrong at all with your BS2 hardware.· Getting your 50 characters or so also indicates the hardware is fine.
  • wolffwolff Posts: 43
    edited 2005-10-24 19:25
    I don't think closing and reopening hyperterm resets the BS2. Are you sure about that?!?
    Also when I look at the serial stream using the debug terminal it does not stop at 50 characters.
  • allanlane5allanlane5 Posts: 3,815
    edited 2005-10-24 20:13
    Yes, I'm pretty sure. Closing the port under Hyperterm drops the DTR signal. Opening the port again raises the DTR signal, which the BS2 BOE board accepts as a reset signal. The BOE board has two capacitors on this line -- one in series, one in parallel -- which keep the high DTR signal from holding the BS2 in reset. However, these two capacitors DO let a pulse through on DTR, which serves to reset the BS2.

    The Debug Terminal knows about DTR, and leaves it low, I believe. It's possible you have hardware handshake turned on with Hyperterm, and that is causing it to cycle DTR, but I doubt it.
  • wolffwolff Posts: 43
    edited 2005-10-25 00:34
    I set the flow control to off. Dosen't that disable all the handshaking and thus the DTR signal?
    Anyway... I downloaded a freeware term program that works GREAT!·· http://bray.velenje.cx/avr/terminal/·· and solves the problem.
    Thanks for your help!
    J
  • allanlane5allanlane5 Posts: 3,815
    edited 2005-10-25 13:37
    Yes, good try. Even though you TELL hyperterm to disable all handshaking, it STILL affects the DTR line. Hyperterm is VERY annoying that it does this.

    The best solution is to use some other terminal program -- and I'm glad you found one that does the job for you.
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