Shop OBEX P1 Docs P2 Docs Learn Events
SX-Key not found on COM1 with SX-Key v3.10 — Parallax Forums

SX-Key not found on COM1 with SX-Key v3.10

Patrick C.Patrick C. Posts: 2
edited 2005-09-08 23:43 in General Discussion
Hi All,

I am using SX-Key v3.10 and when I try to Program my SX52BD I get a message "SX-Key not found on COM1".
I have a SX-DEV kit from SVTEHS and I can program my SX52 when I use the SX-TIPS software.
It seems to be a software problem...
If someone could tell me what is wrong, it would be great.
Thank you,

Patrick

Comments

  • Jon WilliamsJon Williams Posts: 6,491
    edited 2005-09-02 11:36
    Do you have power to the board? The SX-Key must be powered (5v) to be detected.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Jon Williams
    Applications Engineer, Parallax
  • Patrick C.Patrick C. Posts: 2
    edited 2005-09-02 13:02
    Yes, the board is powered with 5V, I use the same hardware settings with the SX-TIPS and the SX-Key is detected.
    I don't know if there is more option in the SX-Key v3.10 software ?

    Patrick
  • Guenther DaubachGuenther Daubach Posts: 1,321
    edited 2005-09-02 14:33
    Is your SX-Key connected to COM1 ? When it is hooked up to another port, select Run-Configure in the IDE, and then the COM port in use.

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

    G
  • SawmillerSawmiller Posts: 276
    edited 2005-09-02 15:18
    i think its more important that he can program sucessfully with the other software prog..
    i still get random "cant find sx key" ..... is there any way to adjust timing ?
    and yes, i am connected to the right com port, have tried another computer, power is on, used usb/serial, and all that, even have a 1000 uF cap accross vdd and vss ( thanks gunther ) still get that error, and it makes it so i have to use sx-sim if i want to debug


    ·
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2005-09-02 16:28
    Hello,

    ·· Is the computer a laptop?· Also, did I see you mention you're using USB/Serial adapter?· If so, what brand?

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Chris Savage
    Parallax Tech Support
    csavage@parallax.com
  • Guenther DaubachGuenther Daubach Posts: 1,321
    edited 2005-09-02 17:02
    To my knowledge, the "SX-Key not found on COMx" error comes up when the IDE tries to establish communication with the SX-Key. To do so, it sends out a connect pattern to the SX-Key, and expects the SX-Key to send back another pattern within a certain time frame. When the IDE does not get this answer in time, it issues this error. I don't think that the time frame has been set too short in the IDE. You can check and provoke this with a normally working SX-Key setup when you click the program button with no serial cable connected to the SX-Key. It will take about two seconds until the error comes up, so I assume that the IDE leaves plenty of time for the SX-Key to answer.

    So, if this error constantly shows up, there must be something wrong, and it can't be a timing issue. There are many possible reasons. Some of them are:

    Wrong COM port, bad serial cable, bad or worn-out connectors, SX-Key pluged on to the ISP pin header in wrong orientation (it will not be powered in this case - but furtunately not damaged, according to my experience), no supply voltage, or voltage out of range (must be close to 5V) up - to the worst case - the SX-Key is defective. I don't think that this is the case with Patrick's SX-Key as he reported that it works with the other software he is using.

    BTW: Here is a trick how to test if the connections between the COM port and the SX-Key are functional: Start up Hyperterminal, or any other terminal program, select some baud rate and format (does not really matter which one), de-select any handshaking options, and turn off any "auto-echo" option, i.e. the terminal program shall not echo the characters you type. Then type in some characters, and you should see them echoed back to the receive window (when each character comes up twice, you did not turn off auto-echo). The SX-Key's COM interface is designed and "hard wired" in a way that it echoes back each character received, no matter if it is powered or not. So, if you see the echoed characters, you can be sure that the hadrware connection between the COM port and the SX-Key is operational, i.e. the plugs and the cable are OK - at least.

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

    G
  • william chanwilliam chan Posts: 1,326
    edited 2005-09-08 13:20
    I have the same problem with "SX-Key not found on COM1" when using v3.1 IDE on my SXKey Rev E.
    I off power, on back again same problem. I pull out the SX Key Rev E. plug in again, same problem.
    I have to repeat the above about 20 times before I get lucky.

    I change to SXKey Rev F. and it just works, almost everytime.
    Same board, same chip, same power supply, same serial cable, same PC, same software.

    However, certain boards with certain SX chip works ok.

    Everytime I complain about this on the forum, they tell me the same old story
    1. Check power supply, make sure it's solid
    2. They don't see a problem with SXKey Rev E.....
  • BeanBean Posts: 8,129
    edited 2005-09-08 13:32
    William,
    I think one problem is that the SX-Key draws alot of current when it first "wakes-up".
    Try putting a cap very close to the Vss and Vdd pins where the key plugs in.
    I have a 10uF cap relatively close and a 0.01uF cap as close as possible to the pins on my video overlay board and I never have a problem, although I do sometimes with the SX-
    Tech board.

    Bean.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "SX-Video·Module" Now available from Parallax for only $28.95

    http://www.parallax.com/detail.asp?product_id=30012
    Product web site: www.sxvm.com
    Available soon!! Video overlay(OSD) module...

    "I'm a man, but I can change, if I have to, I guess"
    Red Green
    ·
  • william chanwilliam chan Posts: 1,326
    edited 2005-09-08 23:43
    Maybe you are right, the next board design I might try that, b'cos some board design usually works well, some other designs I definitely have to use SXKey rev F.
    But I am also sure that there are significant differences between SX Key Rev. E and SKKey Rev. F which nobody will admit to.

    About current consumption, sometimes when I plug in any SXkey with power already on, it can go into a latchup mode, taking 3 times more current than usual.
    I can see the LED on the power rail go dimmed when that happens. ( 7 percent of the time )
    In this mode, it cannot program anything. I have to quickly cut the power, wait a while and then power on again.

    But overall, the SXKey is well designed and robust b'cos it never dies no matter how you abuse it.

    cool.gif
Sign In or Register to comment.