(From the original PR text by @MX-Master)

I have some files for those people who wants to make a quick test of GPIO driver with Orange Pi One board. 

I made two MicroSD images (8Gb, 16Gb) with a couple of HOWTO files. MicroSD image - it's Debian Jessie (built by Armbian) with real-time kernel (4.13, RT-PREEMPT), 
with Machinekit and some tweaks installed:

8GB image
http://topcnc.ru/opi1_cnc/opi1_machinekit_8G.rar

16GB image
http://topcnc.ru/opi1_cnc/opi1_machinekit_16G.rar

HOWTOs:

Hardware.pdf
http://topcnc.ru/opi1_cnc/1%20-%20Hardware.pdf

Copy SD image to SD card.pdf
http://topcnc.ru/opi1_cnc/2%20-%20copy%20SD%20image%20to%20SD%20card.pdf

Control.pdf
http://topcnc.ru/opi1_cnc/3%20-%20Control.pdf

Remote Control.pdf
http://topcnc.ru/opi1_cnc/4%20-%20Remote%20Control.pdf

Machinekit, LinuxCNC and GPIO.pdf
http://topcnc.ru/opi1_cnc/5%20-%20Machinekit,%20LinuxCNC%20and%20GPIO.pdf

Wiring.pdf
http://topcnc.ru/opi1_cnc/6%20-%20Wiring.pdf