Quote Originally Posted by Neale View Post
BTW, on the subject of Arduino power - I'm pretty sure that the Uno spec says that it is happy with 7-12V as it has onboard regulation to give 5V for the Atmega chip, etc. I think my Sanguinololu 3D printer controller (that dates me...) uses 12V. I'm in the process of developing an Arduino-based controller for a different kind of machine at the moment, which is why I was looking this up on the Arduino site a couple of nights ago. It may be that the shield does not pass its power to the Arduino purely because its acceptable input voltage range exceeds what is acceptable by the Arduino.
Yeah, the most likely reason is the variable input. While the RAMPS is designed specifically for 12V without modding, this board takes 12-36V so it's not a simple matter stepping down the voltage for the Arduino. Saying that... I've previously bought a whole load of really cheap £0.99 tiny little boards that take 5636V and transforms it into 5V then through a USB socket. These boards are about the size of a postage stamp and do the job. So actually building one into the board wouldn't cost much...
I think therfore that it's just not been upgraded as both that and SD and screen support should be decently simple for someone with the know-how.

I really love the open source market in some ways, I'm just not able to contribute to that in any meaningful way... yet. I try to think outside the box and take different approaches with my machines for the sake of expanding the database and share that information where I can though :)