3 Replies Latest reply on Feb 19, 2017 2:20 AM by AlexT_Intel

    Error in current edison kit for arduino hardware guide? (GPIO214/TRI_STATE_ALL)

    Elspin

      In section 3 of the current hardware guide for the arduino breakout board, the following text is below Table 3 in section 2.2:

      "Before setting up any muxing, set pin 214 (TRI_STATE_ALL) to HIGH, make all of your changes, then set pin 214 to LOW."

      In section 11 though, it appears to completely contradict with all examples appearing to set 214 to low then high, such as the following:

      # echo 254 > /sys/class/gpio/export
      # echo 222 > /sys/class/gpio/export
      # echo 214 > /sys/class/gpio/export
      # echo low > /sys/class/gpio/gpio214/direction
      # echo high > /sys/class/gpio/gpio254/direction
      # echo in > /sys/class/gpio/gpio222/direction
      # echo mode1 > /sys/kernel/debug/gpio_debug/gpio182/current_pinmux
      # echo high > /sys/class/gpio/gpio214/direction
      

      It seems fairly important to get this right, but I've searched the communities and I'm seeing examples all over that do it either way which is really not helpful. I'm leaning towards section 11 just being full of errors as the changelog states "Reversed high-low sequence of gpio214 in shield pin configuration section." in 2014, maybe section 11 just wasn't updated? Would appreciate clarification on whether I'm just confused on how linux represents the setting of high/low for signals or if there's clear errors in the manual (in which case, please update it intel!)