The power enable signal USBH_EN is shared with the all three other host interfaces USBH2,
USBH3 and USBH4. If USB bus power supply needs to be switched individually for each port, any
free pin with GPIO functionality could be used to control the USB power rails individually. In this
case the USB driver needs to support such an implementation.
The USBH_OC# signal is shared between all the USB host ports of the Apalis. Since the signal is
open drain type, it can be connected directly to the all overcurrent output ports. The signal requires
a pull-up resistor on the carrier board.
Figure 29: USB 2.0 host reference schematic
2.5.3 Unused USB Signal Termination
Leave NC and set the USB port direction in software to host or client OR ground the pin if port is
used permanently as host OR add pull-up resistor if port is used as slave.
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