|m3pi USB A connector.|
The m3pi expansion PCB has space for a USB A connector that connects to the mbed’s USB pins (D+ and D-). The fully-assembled m3pi robot ships with the USB A connector soldered to the PCB; the m3pi expansion kit includes this connecor, but it is not soldered in.
The USB A connector allows the mbed to act as a USB host and interface directly with USB devices. For example, you could plug a USB flash drive into your m3pi and have your robot log data to it as it drives around. This connector is only required if you want to use your mbed as a USB host; it does not serve the same function as the mbed’s mini-B USB connector, which is used to program the mbed.