Hello guys,I have been trying to get into gcode recently and I have found Tinkernut´s CR-Rom to cnc tutorial (Hack old CD-ROM's into a CNC Machine - Part 2: The Software - YouTube) .Hardware part is ok but when I use XLoader to load hex file v0.8c from site GitHub - grbl/grbl: An open source, embedded, high performance g-code-parser and CNC milling controller written in optimized C that will run on a straight Arduino my motors starts to go 1 side forever.
Only difference from video is that I use USB to power and H-Bridge to control motors.
Any help please?
Thank you for your time 
Btw when I use standart arduino code all works well..So no problem in circuit itself.
It is usually a bad idea to power an Arduino and some motors from the same source. Certainly, most motors should not be powered by USB. Provide some other power source for your motors.
A video shows things working properly. You do the same as the video but with some differences AND things do not work so well. Could there be a connection?
Hey man thank you for reply.So I did connected motors to separated power sup. and motors seems to be working better BUT when I send code G0 z-1 (moves z axe up) but when I tell it G0 z0 nothing happens..and thats same for all motors 
Any wise help again please
I am glad to help but I do not know grbl and I do not know gcode. Sorry!
In any case, this probably deserves a new post with a different title.