As for the hardware, you could look at the schematics of the Lego Mindstorms NXT for reference. It is compatible with these old sensors, which can be connected to pins 1 and 2 of the sensor ports:


Go to the support page for the NXT.
Get the Hardware Developer Kit (no link due to badly designed web page).
Look at the schematics for the main unit in Appendix 1.
The pins 1 of the sensor ports are handled by an ATmega48, take a look at ADC_A0 to ADC_D0 for the inputs and I_ONA to I_OND for power control. Sensor port pin 2 is ground.
The power control circuit contains an extra PNP transistor for current limitation, that may be overkill for you.


When turned on the sensors are powered by the full battery voltage for most of the time, they are only powered off briefly for doing each measurement (I think the 0.1ms by jme are correct). Standard is to do a measurement every three ms.

Lego Color Sensor + Arduino
I am working with a polygon that is the result of a buffer and has a bunch of internal doughnut holes:
 What I want is this: 

I am using arcpy.EliminatePolygonParts_management() to fill in the holes but have a question about how this tool functions.

When I run the tool using the "PERCENT" condition I cannot get the holes to fill in.  Initially I set the percent to 99 thinking that it would delete any part that was smaller than 99 percent of the total area of the polygon.  That didn't work.  Thinking that perhaps I had my logic backwards I set the percent to 1, that didn't work either.

I did get it to work, and produce a polygon that is just the outer boundary but to do so I had to switch to the AREA condition and set the number ridiculously (for my purposes) high, to 1 billion square meters.

I am quite confused by this...  Can anyone offer an explanation to help clarify my understanding of how this tool works and why I can't get the "PERCENT" condition, which seems to be the more appropriate choice, to work?
