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USB DIRECTOR/4-PORT HUB
4. Operation
The USB Director/4-Port Hub is an extension of the
host’s USB bus. You only have to plug it into the host
USB connector to operate. The hub is hot-pluggable;
you can plug it in at any time, even when the host PC is
powered on. When attached, the operation is automatic.
The host software will detect that a device has been
attached to the USB bus, query the device to identify it,
and load the appropriate driver. The hub driver will
then enable the hub and each of the ports. If the hub
detects a device attached to the port, it will notify the
host. The host will then communicate with the device to
identify it and load its device driver. (This function may
vary depending upon the individual device.)
The Hub has power on/off, overcurrent reporting, and
suspend/resume controls for the hub as well as for each
of the individual ports. The host can send a command to
turn on or off the hub, and individual port, or a device
attached to the port. Suspend is a global or individual
device command that sets the device or hub into a
low-power mode where it is virtually powered off
(<500 microamps), yet allows a device to request a
remote wakeup. A wakeup will be responded to with