Touch Screen 4 wire Driver RRS feed

  • Question

  • I'm working by FriendlyARM 6410 embedded system. The touch of this board
    can work in two mode: 1-wire and 4-wire. In 1-wire mode, a micro controller
    as interface convert 4-wire data to 1-wire data. For a commercial
    application, we want to work in 4-wire mode.
    But in the 4-wire mode, the touch doesn't work well as the 1-wire mode.
    For example, double-click worked hardly. It seems, the CPU sometimes is
    busy and touch events received by delay. However, I analyzed the touch of
    another embedded system TQ6410 with same CPU in the 4-wire mode. The touch
    of this board worked fine. I copied the touch driver code and registry
    settings of the TQ6410 to the FriendlyARM. But it makes no difference. The
    touch functionality does not improve and it still does not work well.
    Anybody can guess the reason of different functionality of touches between
    these two boards? As regards,they both have same touch driver and same CPU.
    Sunday, December 23, 2012 12:28 PM

All replies

  • I guess its the debounce issue...

    1 bit data transfer is slower than 4 bit.

    If things works well in 1 bit mode may be you increase the debonce a bit and check ...

    You can also measure the rate at which you are getting touch data in 1 bit mode and 4 bit mode and accordingly adjust the debounce.

    --- Misbah

    Senior Design Engineer T.E.S Electroni Solutions (Bangalore-India)

    Tuesday, December 25, 2012 7:09 PM