Using SUB-20 for automated cables testing

[xol]

Let's take hypothetical 3-wires cable and connect it to SUB-20 GPIOs this way:

GPIO0 --- wire0--- GPIO1
GPIO2 --- wire1--- GPIO3
GPIO4 --- wire2--- GPIO5

First test connectivity
--------------------------
1. Set GPIO 0,2,4 to output
2. Set GPIO 1,3,5 to input with internal pull-up
http://www.xdimax.com/sub20/doc/HTML/su ... config.htm
3. Set GPIO 0,2,4 High and read GPIO 1,3,5 to be High
4. Set GPIO 0,2,4 Low and read GPIO 1,3,5 to be Low
http://www.xdimax.com/sub20/doc/HTML/sub_gpio_write.htm
http://www.xdimax.com/sub20/doc/HTML/sub_gpio_read.htm

Second test shorts between wires
---------------------------------------
1. Set GPIO 0,2,4 to output
2. Set GPIO 1.3.5 to input with internal pull-up
http://www.xdimax.com/sub20/doc/HTML/su ... config.htm
3. Set GPIO 0,2,4 High
4. Set GPIO 0 Low and read GPIO 1 to be Low, while GPIO 3,5 are High
5. Set GPIO 2 Low and read GPIO 3 to be Low, while GPIO 1,5 are High
6. Set GPIO 4 Low and read GPIO 5 to be Low, while GPIO 1,3 are High
http://www.xdimax.com/sub20/doc/HTML/sub_gpio_write.htm
http://www.xdimax.com/sub20/doc/HTML/sub_gpio_read.htm