Template:FAQ/Questions/there three power inputs

Why are there THREE power inputs when there are only two things to be powered: the gumstix and the servos?
On the robostix board, V_BATT isn't an input. The 3 inputs are:


 * 1) V_POWER (same type of power connector that's on all of the other boards). This allows the gumstix/robostix to be plugged into the wall wart.
 * 2) V_ROBOBATT - really the same as V_POWER, but it's a 2 pin 0.1&quot; header, rather than a jack like the one on the wall wart. You would only ever use one of V_POWER or V_ROBOBATT at the same time.
 * 3) V_MOTOR - goes to the servos.

There is a jumper which allows V_MOTOR/V_ROBOBATT to be connected together which results in the motors and the ATMega being powered from the same battery (connected to either battery connector or the wall-wart plug).