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sx key pc communication error; sx key not found in Com 1 error message — Parallax Forums

sx key pc communication error; sx key not found in Com 1 error message

nimoeheartnimoeheart Posts: 2
edited 2011-03-16 04:11 in General Discussion
I am using sx key rev F to load to an sx 28 and I keep getting the same communication message no matter what I do.
I have verified that it is·in port com 1 (I only have 1 com port). I have verified that my sx key IDE configuration shows that it should look for the sx key there, which it·appears to be doing.
I have uninstalled and reinstalled drivers for my com port twice. I have verified through the device manager that the com port is running correctly. Don't know what else to do.

Comments

  • Guenther DaubachGuenther Daubach Posts: 1,321
    edited 2007-10-21 14:00
    On my PC, I have one COM port (COM2) with a defective output driver. Nevertheless, device manager reports that COM2 is available, and so does the SX-Key IDE, as both can't "know" about the broken output driver, so this is not a guarantee that a COM port is really working. So please try the following tests:

    First Test:

    On the PC, launch a terminal program, like HyperTerminal, and set it up to use COM1 at 57600,8,n,1, no flow control, and finally, open the connection to let HyperTerminal send and receive characters.

    Now connect the SX-Key to the COM1 port but do NOT connect the SX-Key to your SX28 system. When you type any characters on the PC, they should be echoed back into the terminal window. When this is the case, you can be sure that COM1 is working, that the serial cable is OK, and that the serial connector of the SX-Key is ok. The reason for the echoes is that the PC's TxD and RxD lines are connected together on the SX-Key via a resistor, so this even works when the SX-Key is not powered.

    Note that some terminal programs automatically echo back typed-in characters. So, when you get echoes without the SX-Key connected to the COM port, either turn off the terminal program's echo option, or expect two echoes for each typed character when the SX-Key is connected to the COM port.

    When this fails, check the cable (must be a stright-through, not a crossed null-modem type), the connectors, and try to connect some other serial device, like a modem to the COM port to verify that it works.

    Second Test:

    Next, also connect the SX-Key to your SX28 system, and power it up. On the PC enter the following text (exact writing, and case, without the Quotes): "SK-Key". As you type the characters, they should be echoed back, and as soons as you have entered the 5th chanracter (the "y"), the text "SX-Key", followed by three random characters should be displayed in the terminal window. When this is the case, you know that the SX-Key does receive characters from the COM port, and that the on-board SX20 is active because it has answered to the connect string ("SXKey") you have sent.

    When this fails, make sure that the power is correct. Between the two header pins marked "Vdd", and "Vss" of the SX-Key connector, you should measure 5 Volts (Vdd is positive).

    What board are you using for the SX28 - an SX-Tech board, any other Parallax board, or your own design?

    Good Luck!

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Greetings from Germany,

    G
  • nimoeheartnimoeheart Posts: 2
    edited 2007-10-21 17:10
    Thanks Guenther,
    ·············· I downloaded a program called Com Inspector and check it that way because the program sounded easier to use. The scan failed and said "recheck all connections." I'm taking that to mean that there is something wrong with my com port. Since I have already uninstalled and reinstalled the drivers for it a couple of times, it would seem that I am out of luck on getting it to work. Any other ideas? Should I just try to work with the SX Blitz. I am pretty sure that's USB...
  • Guenther DaubachGuenther Daubach Posts: 1,321
    edited 2007-10-21 20:12
    Yes, the new SX-Blitz is a USB device, so no real COM port is required (just the virtual COM port USB driver). As long as you only want to program the SX, the Blitz is fine, but you can't debug the SX with the Blitz.

    An alternative is a USB/Serial converter, like the USBto232 device from Parallax. This allows you to connect the SX-Key to a USB port. Maybe, you have a chance to attach the SX-Key to another PC to make sure that it is OK before buying such an adapter.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Greetings from Germany,

    G
  • andand Posts: 7
    edited 2011-03-16 04:11
    Hi
    Have you found a solution to this error. I have experience this error on Windows Vista and got around it by changing the compatibility mode to win98. which solve the comms problem.
    But an Windows 7 the error occurs and does not got away using the above steps
    Andrew
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