Is this new? Just got an email from inventables…
CNC Motion Controller
Our USB Motion Controller offers an easy, low-cost way to use the Mach3 CNC Controller on a PC without a parallel port.
https://www.inventables.com/technologies/usb-motion-controller?utm_source=MadMimi&utm_medium=email&utm_content=Powerful+New+CNC+Accessories&utm_campaign=20140501_m120236850_New+CNC+Controller+and+Stepper+Driver&utm_term=Check+it+out_21_E2_86_92
It’s new to them, i think they just started carrying it.
The controller called a UC100, and does exactly what it says: allows one to run mach3 via USB.
Keep in mind, the product only works with mach3.
You can read more about it in my buildlog on the shapeoko forum: http://bit.ly/1iNEUj2
What does mach3 give me if I am already running grbl or tinyg?
First: Mach3 is a completely different control program, windows based, that requires a different controller to operate. Traditionally mach3 uses a PC with a parallel port to talk directly to a stepper motor controller such as the TB6560, xylotec, or hobbycnc boards, to name a few.
This little adapter lets you do all of that,except without the parallel port.
Mach3 is also a more mature program (it’s been around since 2001) and is capable of more advanced features than you will find on the current grbl or tinyG builds.
To name a few: there is a built in programming environment, a huge selection of plug-ins that provide additional functionality, and conversational programming which lets you perform common tasks (like facing, hole patterns, pocketing, etc) through the console instead of a CAM program.
-Edward
Mach4 will be out soon…
Soon is a relative term. http://www.machsupport.com/software/mach4/
@Edward_Ford thank you for the info. Wouldn’t LinuxCNC have those features you mentioned as well that differentiate Mach3 and grbl-based solution?
Yes, LinuxCNC has a similar set of features. At this point in time thought, there isn’t a widely available or proven USB solution (such as the adapter in question). So you’ll more than likely need a PC with a parallel port in order to utilize linuxcnc.
-Edward
@Dat_Chu
Mach3 and Linuxcnc both forked from the same source code. The original NIST EMC software. Although to look at them both today one might never know it.
Interesting. I have no idea. Mostly since I am very newbie to cnc and have been rather content with grbl.
That’s what this group is for right? 
@Dat_Chu That and posting pictures of half naked pot bellied lathe workers in India…