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  • Gen4-4dcape-70ct-clb

    i have the following 7" screen and cape for BBB : GEN4-4DCAPE-70CT-CLB
    when connected and powered i can see the back light come on underneath the screen + a green light (but the screen is basically dark and nothing is shown)
    I have been using my BBB for CAN-bus-communication for a year and uses P9.24 and P9.26 for Rx/Tx. this is fixed and must be used for my project.

    I can also see that P9.26 is used by 4D systems for a touch interrupt on gpio_14

    would this simple conflict be enough to stop my screen working like this ? is this the problem ? (i have no clue and been trying to get the screen working this weekend)
    should the screen work if the pin is removed physically from the cape ? but i guess the touch screen will no longer work and that would not be ideal

    is it somehow possible to cut the pin from the cape and rewire to another / reassign ?

    or have i made a mistake getting this screen for the intended use with a CANbus project ?

    thanks for any ideas / response.

  • #2
    oh not sure if this is reliant but i am using Debian 8.3 2016-01-24


    • #3

      Welcome to the Forum.

      I have tried your idea of cutting the P9.26 and it indeed makes the display untouchable (I first used a pair of stackable headers so the adaptor won't get unusable).

      As of now, I don't see a solution yet for Capacitive touch capes to make the display work with cut P9.26, but there is a way for resistive touch displays.

      To make the touch function again, I used the command:

      $sudo modprobe ar1021_i2c
      Click image for larger version

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      Will find more if I can make the capacitive touch work and let you know.

      Hope this helps and Best Regards,