CAMBRIONIX ThunderSync2-16, Руководство пользователя

Страница: 14 / 37

Thundersync2-16 Page 13 of 35
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.