The Baby Orangutan is powered via the VIN and GND pins, which are located at the top-right corner of the board. The device is protected by a MOSFET against accidental reverse-battery connection. The supply voltage should be 5 – 13.5 V, with an absolute maximum of 15 V, so a 5- to 9-cell NiCd or NiMH battery pack is a good choice. This Orangutan can work with a 10-cell NiCd or NiMH battery pack or a 12V lead-acid battery, but you should be aware that such a power source might exceed the controller’s maximum voltage rating if the batteries are freshly charged. When the Orangutan is powered, the green power LED is illuminated. The RESET pin can be brought low to reset the controller, but it can otherwise be left disconnected (it is internally pulled high).
Please see the Pololu AVR Programming Quick Start Guide for tutorials on how to get started programming the Baby Orangutan in Windows, Linux, and Mac OS X. That guide also covers the Pololu AVR C/C++ Library and the Pololu USB AVR Programmer.