CAMBRIONIX TS2-16, Руководство пользователя

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TS2-16 Page 14 of 36
5.3. Scalability
USB controllers generally have an endpoint limit, limiting the number of devices that can be
enumerated when connected to the USB3 port of a local computer. USB3 port xHCI host
controllers in most computers limit the number of endpoints enumerated between 64 and 128.
Mobile devices enumerate as more than one endpoint, and complex devices with touch panels
often enumerate as 5 or 6 endpoints. Consequently, the number of devices that can be
successfully enumerated is typically limited to less than twenty.
By using Thunderbolt™ connectivity and incorporating host controllers inside the hub each port
can handle up to 16 endpoints. If you wish to synchronise more devices, multiple hubs can be
daisy-chained to allow up to 96 devices to be managed simultaneously from a single host
computer.
To daisy-chain multiple hubs, each hub needs to be connected to mains power individually,
then the first hub in the chain should be connected to the local computer through one of the
Thunderbolt™ ports. The next hub in the daisy-chain is connected using one of its
Thunderbolt™ ports to the remaining Thunderbolt™ port of the first hub. A third, fourth and
fifth hub can be added in the same way, connecting the available Thunderbolt™ port of the
previous hub to one of the Thunderbolt™ ports of the next device in the daisy-chain. Using this
approach, a maximum of six hubs can be linked together, allowing 96 devices to be synced from
a single host computer.