GPy + Pytrack startup connection issues

  • Re: GPy Initial Startup Connection Issues


    First of all, this is my hardware:

    • GPy 1.0
    • Pytrack v1.1
    • Macbook Pro early 2011 with MacOS High Sierra

    The software I'm using

    • Atom with Pymakr 1.4.10

    The problem: when connecting the GPy (on a Pytrack) the Macbook doesn't recongnize it, in the System information windows doesn't appear any new device connected and the pymakr can't connect to the GPy. After one or few resets (sometimes) it comes alive and the pymakr can connect, and all works fine. This is randomly, sometimes I reset a lot of times the GPy but nothing happens, the Gpy never comes alive. I have two GPy boards and two Pytrack boards and these do the same thing.

    I've noticed it seems a trouble when the GPy is on the Pytrack, because if I connect the Pytrack only then it is recognized by the Macbook and Pymakr also. But with Pytrack + GPy this don't work at all.

    The firmware is updated in both, the Pytrack and GPy boards. The documentation says no drivers are needed in MacOS systems, and it don't seems a driver problem since the boards sometimes works after a few resets.

    Any suggestions? what can I do to get GPy works fine without making resets everytime I use the board?

    Thanks in advance.

  • --- Edit ---
    Nevermind. The same problem occured again after a few hours. See my current thread on bridging P3 to GND for a possible solution.
    --- End Edit ---

    @jchernandez Hi, I came across the same problem just now and managed to solve it:

    For me, the problem first occurred after I accidentally disconnected a GPy and PyTrack from USB. The GPy would work with the PWR_EN removed, like yours. Other board and shield combinations would work, too.

    What resolved the problem was re-flashing the pytrack firmware from the dfu file. Now everything works again without pin modifications.

  • Confirmed, I've connected all pins except P3 and the Pytrack + GPy is recognized by Macbook and Atom and work fine immediately! No more resets needed!


    What is the PWR_EN pin on the Pytrack for?

  • I've been trying to fix GPy + Pytrack problems today but no succes yet

    The next is what I have been testing

    • Pytrack only (with no GPy board) is always recognized by Macbook
    • GPy only with a USB to serial adapter is always working when connecting to the Macbook

    When connecting the Pytrack and GPy through jumper cables, and connecting only Vcc, GND, Tx and RX... it WORKS!


    I think is a problem of GPy pinout configuration, some kind of shortcircuit happens because when measuring the Vcc voltage in the Pytrack (without GPy) it is a stable 4.78V. But when GPy is on the pytrack the Vcc voltage becomes unestable between 0 - 2.5V


    So, I was adding jumpers cables to connecting others pins from the GPy board to the Pytrack and when the P3 is connected the Vcc voltage becomes unestable. On the Pytrack side the documentation says this pin is "PWR_EN" and when measured with multimeter it is 3.3V. On the GPy the documentation says it is by default TX1, and the pin also has 3.3V

    I made downgrade to the GPy firmware, but all has the same results, tried these versions

    • GPy-1.18.1.r4
    • GPy-1.18.2.r1
    • GPy-1.18.2
    • GPy-1.19.0.b5

    I keep trying to make these two guys work together!

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