question: What does the USB specification require prior to the Battery Charging Specification ?
answer: that devices connect in a low-power mode ( 100 mA maximum ) and communicate their current requirements to the host
turker_answer: The USB specification requires that devices connect in a low-power mode ( 100 mA maximum ) and communicate their current requirements to the host prior to the Battery Charging Specification .
rule-based: The USB specification requires that devices connect in a low-power mode ( 100 mA maximum ) and communicate their current requirements to the host prior to the Battery Charging Specification .