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BASIC STAMP USB to SERIAL — Parallax Forums

BASIC STAMP USB to SERIAL

SpanierFIUSpanierFIU Posts: 6
edited 2008-02-04 07:01 in BASIC Stamp
Computer does NOT recognize the USB connection thru the serial cable. It appears in the Device manager,
but BASIC STAMP Editor software doest NOT recognize the BASIC STAMP.

Please advice ASAP. Thank you

Comments

  • DosEdgeDosEdge Posts: 33
    edited 2007-11-09 15:17
    First, I will like to ask, do you have the USB driver installed? Does it appear unknown according to the Device manager?
  • SpanierFIUSpanierFIU Posts: 6
    edited 2007-11-09 15:34
    The driver has been installed and device manager recognizes the device. When I try to "identify" loopback and echo say yes, but the device column stays blank. When i try to run a basic program, it says no basic stamp found.

    Thanks for the quick response.
  • Mike GreenMike Green Posts: 23,101
    edited 2007-11-09 15:59
    Loopback simply indicates that a jumper is present between DSR and RTS. Echo means that the Stamp is physically present because the programming circuitry on the Stamp echos any received characters back to the PC, but the Stamp processor doesn't have to be working.

    Check that there's power applied to the Stamp. The Stamp processor has to actively communicate with the PC to tell it its version (for Identify to work).

    What kind of USB to serial adapter are you using. Some do not implement all the signal lines properly (DTR in particular has to work properly). Sometimes the timing in the driver adds enough in the way of delays that the PC doesn't recognize the Stamp.
  • SpanierFIUSpanierFIU Posts: 6
    edited 2007-11-09 16:01
    The stamp is being powered by 9 VDC via a power supply.
  • SpanierFIUSpanierFIU Posts: 6
    edited 2007-11-09 16:24
    I am using the Prolifif USB-to-Serial Cable. Prolific Driver date 7.16.2003.

    Port Settings:

    Bits per second: 9600
    Data bits: 8
    Parity: None
    Stop bits: 1
    Flow Control: None

    Advanced..

    Use FIFO buffers enabled

    Receive buffer: High (14)

    Transmit buffer: High (16)
  • Mike GreenMike Green Posts: 23,101
    edited 2007-11-09 16:35
    Try disabling the FIFO buffers or making them smaller. Sometimes the delays will interfere with the timing of the communication back and forth.
  • Peter VerkaikPeter Verkaik Posts: 3,956
    edited 2007-11-09 16:36
    I have a Prolific USB2SER cable that works. Chipset PL2303H.
    Drivers for XP (Vista not supported):
    http://www.prolific.com.tw/eng/downloads.asp?ID=31

    regards peter
  • SpanierFIUSpanierFIU Posts: 6
    edited 2007-11-09 19:41
    I already tried disabling the FIFE buffers. no cigar. i then used the driver Peter suggested and now its says the port is invalid.
  • Mike GreenMike Green Posts: 23,101
    edited 2007-11-09 21:20
    I suggest you call (or e-mail) Parallax tech support on Monday. The Stamp editor works fine for me on several machines under Windows XP with both the Keyspan and FTDI USB to serial adapters and it has worked fine in the past under Windows 98SE as well. Sometimes these things are just a little too complicated to work out using a forum for communications.
  • SpanierFIUSpanierFIU Posts: 6
    edited 2007-11-09 22:37
    Thank you for your help. I'll contact Parallax on Monday.
  • Sens-a-DatSens-a-Dat Posts: 44
    edited 2008-01-30 14:17
    Mike, you indicated earlier that "Echo means that the Stamp is physically present because the programming circuitry on the Stamp echos any received characters back to the PC, but the Stamp processor doesn't have to be working." I was able to obtain an ECHO from the circuitry with a Stamp being present. The echo is being produced because of the 4.7K resistor connecting pins TXD and RXD from the DB9 connector.
  • saharadja12saharadja12 Posts: 5
    edited 2008-02-03 16:46
    did you find any solutions Spanier??

    ive got the same problem as you did

    [noparse]:([/noparse]
  • Mike GreenMike Green Posts: 23,101
    edited 2008-02-03 17:03
    saharadja12,
    It is very unlikely that the problem is with the Stamp or the Stamp Editor. You really have to go carefully through the other items:
    1) Do you have a proper USB to serial adapter or a real serial port on your PC? It must implement the DTR signal.
    2) Do you have the proper USB to serial I/O driver installed properly?
    3) Do you have a "straight through" serial cable with DTR implemented?
    4) Do you have proper power supplied to your Stamp?
  • saharadja12saharadja12 Posts: 5
    edited 2008-02-03 18:32
    hi mike

    proper power supply = check

    ive tried to install the usb-serial converter driver provided by cliptec (www.cliptec.com) but it does not recognized by windows but hopefully the recent driver is compatible enough

    if the DTR checkbox is checked but CTS is not lit (BS editor debug terminal), does it means that the converter did not implement DTR signal?

    thanks
  • Mike GreenMike Green Posts: 23,101
    edited 2008-02-03 22:24
    The only way you can tell for sure if DTR is implemented is to have a program that turns it on and off and to actually look at the signal line using an oscilloscope. I looked at Cliptec's website and they have very little information available. I would take that to mean that they likely have not implemented the control lines properly. Most manufacturers that have done so would want to make it clear that have because it's uncommon.
  • saharadja12saharadja12 Posts: 5
    edited 2008-02-04 07:01
    finally

    theres nothing wrong with my serial converter..the problem is with the voltage supplied.
    i found out that there is voltage drop from 4.5v to 4.48v when the supply is connected to BS2, which i thought was ok to operate the stamp.
    then i increase the supply voltage to 6.0v (voltage drop at 5.98v) and walla, my BS2 is alive ahhaha

    thanks for your help [noparse]:)[/noparse]
    and happy stamping

    best regards
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