SoC processors have several built in controllers on the CPU. For instance, you'll typically see: a flash controller, an ethernet controller, one or more UARTs,

SoC processors have several built in controllers on the CPU. For instance, you'll typically see: a flash controller, an ethernet controller, one or more UARTs, i2c controller, DRAM controller, etc. Development boards break out all of these controllers to external interfaces. The OMAP-L138 Processor only supports usb 1.1 and usb 2.0. In general, a fair number of low power processors in the PDA/netbook realm only support usb 1.1. It may be possible to use an external usb 3.0 controller but that would dramatically complicate your board design.