TS-TPC-7990 USB Host
From embeddedTS Manuals
The TS-7990 provides 4 standard USB 2.0 host supporting 480Mb/s. Two are on the Type A connector, one is on the XBEE module for use with cellular MODEM modules, and one is on the mini PCIe header. Most commonly USB drivers built into Linux handle the USB communication but low level USB communication is possible using libusb.
A GPIO is available to toggle power to USB devices. This can be used to save power, or to reset USB devices that get stuck in a bad state.
# Power disabled
echo 0 > /sys/class/leds/en-usb-5v/brightness
sleep 2 # let any devices reset
# Enable power
echo 1 > /sys/class/leds/en-usb-5v/brightness