TS-4900 USB Host: Difference between revisions
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Many of our off the shelf baseboards provide a GPIO 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. | Many of our off the shelf baseboards provide a GPIO 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. | ||
<source lang=bash> | <source lang=bash> | ||
# Power disabled | # Power disabled | ||
echo | echo 1 > /sys/class/leds/en-usb-5v/brightness | ||
sleep 2 # let any devices reset | sleep 2 # let any devices reset | ||
# Enable power | # Enable power | ||
echo | echo 0 > /sys/class/leds/en-usb-5v/brightness | ||
</source> | </source> | ||
{{Note|The USB OTG which can act as a host does not always use the same controllable 5V supply. Refer to the schematic's EN_USB_5V/USB_5V for more information on this control.}} | {{Note|The USB OTG which can act as a host does not always use the same controllable 5V supply. Refer to the schematic's EN_USB_5V/USB_5V for more information on this control.}} | ||
Revision as of 17:54, 1 October 2014
The TS-4900 provides a standard USB 2.0 host supporting 480Mb/s. Typically this is interfaced with by using standard Linux drivers, but low level USB communication is possible using libusb.
Many of our off the shelf baseboards provide a GPIO 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 1 > /sys/class/leds/en-usb-5v/brightness
sleep 2 # let any devices reset
# Enable power
echo 0 > /sys/class/leds/en-usb-5v/brightness
| Note: | The USB OTG which can act as a host does not always use the same controllable 5V supply. Refer to the schematic's EN_USB_5V/USB_5V for more information on this control. |