Arduino Com port has disappeared

If you're having trouble with your LattePanda, here's the place to get help.
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    User avatar
    Tempest8008
    Posts: 25
    Joined: Tue Sep 12, 2017 3:42 pm

    Wed Feb 14, 2018 8:50 pm

    We're using a case where it will be a sealed unit that the customer won't be expected to open it.

    I brought this up over in one of the other forums too, but no one seems to want to answer the question.

    Can the Arduino on the LattePanda be reset via software to solve this COM port issue? Or is there something else that can be done with a pin where we bring it high or low to reset the Arduino?

    User avatar
    LattePanda
    Site Admin
    Posts: 2661
    Joined: Wed Jan 20, 2016 9:09 am

    Sat Feb 24, 2018 9:14 am

    I did some quick research. You need to set DTR and reopen the com port via a script or some specific software.

    And I find this python code for that purpose:

    My Python script to reset a Leonardo is like this:

    Code: Select all

    import serial
    import sys
    ser = serial.Serial()
    ser.port = sys.argv[1]
    ser.baudrate = 1200
    ser.open()
    ser.setDTR(0)
    ser.close()
    Link: https://github.com/sudar/Arduino-Makefile/issues/30
    Enjoy Tinkering with LattePanda ! :lol:

    User avatar
    CIM
    Posts: 2
    Joined: Wed Apr 11, 2018 3:28 pm

    Wed Apr 11, 2018 3:55 pm

    We are LattePanda newbies, trying to load the "blink" test to check out the methods and systems. We have Visual Studio 2017, and a 2Gb/32Gb board running Windows 10.

    When we try to upload a sketch such as Blink, not only does the port change, sometimes it disappears (greyed out) in the serial port setting in Arduino. We have read through the blogs, pressed reset, powered up and down, tried all of the sensible and useful things, and it still happens. Running the application throws an exception when VS can't find the port.

    Back in the bad old days when 100 lines of tested machine code was a good day's work, this kind of problem was expected, and a lot of people died because of it, which is why we went to the trouble of designing high level languages and decent operating systems, and most importantly, good documentation.

    As users, this is not our problem, it sits firmly with the manufacturer / supplier. It is a fundamental system bug, not finger trouble, and it shouldn't happen. So how's about somebody from LTP actually fixes it, instead of just reading the blogs? Our intended application is airborne, and we can't tolerate bugs like this. So before we toss the LattePanda into the bin (plus getting our money back) and switch to a conventional mini PC (pity, because the hardware format and the capability of running VB.Net (our main support language) is very attractive). We would be happy to help find the problem, but the documentation is so poor that we don't have enough platform info to even make a start.

    Thanks in anticipation ........

    User avatar
    LattePanda
    Site Admin
    Posts: 2661
    Joined: Wed Jan 20, 2016 9:09 am

    Tue Apr 17, 2018 9:27 am

    Hey, how's everything going?
    Enjoy Tinkering with LattePanda ! :lol:

    User avatar
    Lemminger65
    Posts: 5
    Joined: Wed Nov 14, 2018 10:44 pm

    Sun Dec 02, 2018 12:29 pm

    Hey admin,
    I have still that problem like here discussed.
    How to solve that?

    Regards, Klaus

    Post Reply