ASUS Tinker Board 2S 設定 GPIO(Using the sysfs Interface)

 ASUS Tinker Board 2S 設定 GPIO(Using the sysfs Interface)

https://tinker-board.asus.com/forum/index.php?/topic/14984-gpio/

方法一：

 Using the sysfs Interface

就是直接對 Linux File System 的 /sys/class/gpio/ 文字檔進行讀寫

方法二：

使用 ASUS 提供的  GPIO WiringPi for C library

https://github.com/TinkerBoard/TinkerBoard/wiki/User-Guide#sample-code-for-tinker-board-2-series

http://dlcdnet.asus.com/pub/ASUS/mb/Linux/Tinker_Board_2GB/GPIO_API_for_C.ZIP

方法三：

使用 ASUS API Programming方式(只有使用範例, 無原始碼)

https://tinker-board.asus.com/tw/documentation/ter.html#api/

方法一說明：

1. 先到wiki 查詢 2S GPIO pin對應到 Linux Debian之Device Path

  (Tinker Board 2S 每一個GPIO Pin 對應到Linux GPIO Index)

  GPIO Config Table for Tinker Board 2 series:

  https://github.com/TinkerBoard/TinkerBoard/wiki/User-Guide#gpio-config-table-for-tinker-board-2-series

  

 例如本次要試驗的是 Tinker Board 2S GPIO pin-18 

  對應到 Debian之Device Path是 GPIO: /sys/class/gpio/gpio87

  

2. 參考網站

  GPIO Programming: Using the sysfs Interface

    https://www.ics.com/blog/gpio-programming-using-sysfs-interface

  風火輪對 /sys/class/gpio 之解釋文

    https://wiki.youyeetoo.cn/tinker/page/DebianSystem/User_GPIO

3. 設定

  $ sudo bluefish /boot/config.txt

    下面這一行 GPIO pin-18 為 spi5 不可以打開

    #intf:spi5=off

4. 指令

    > Device Path是 GPIO: /sys/class/gpio/gpio87

    $ sudo su

    $ cd /sys/class/gpio

    $ echo 87 >/sys/class/gpio/export

    $ ls /sys/class/gpio/gpio87/

    $ echo out >/sys/class/gpio/gpio87/direction

    $ echo 0 >/sys/class/gpio/gpio87/value

     > 電錶量測 Tinker Board 2S GPIO pin-18 會是 0 

    $ echo 1 >/sys/class/gpio/gpio87/valu

     > 電錶量測 Tinker Board 2S  GPIO pin-18 會是 3.3v

5. C/C++ Example

   How to Control GPIO Hardware from C or C++

   https://www.ics.com/blog/how-control-gpio-hardware-c-or-c

   https://github.com/tranter/blogs/tree/master/gpio/part5