A cordless power tool may include tool identification circuitry to provide a tool identification signal to a battery pack. The tool identification signal may be representative of data particular to the cordless power tool. A method may include coupling a battery pack to a cordless power tool, and providing a tool identification signal to the battery pack from the cordless power tool once the battery pack is coupled to the cordless power tool, the tool identification signal representative of data particular to the cordless power tool.