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724-746-5500 | blackbox.com
Page 9
Chapter 4: USB-Related Issues
4. USB-Related Issues
4.1 Fast Switching of USB
In Version 2.6 of Agility dual firmware, we implemented fast switching USB. This is the implementation of the final piece of our
USB True Emulation technology, which we have developed on products like the ServSwitch Freedom and ServSwitch Wizard DVI
DL.
The TX units now store information about the USB devices they have connected and continue to report them to the host
computer even when the receiver has disconnected. This means that the host computer doesn’t tear down its USB link if an RX
unit switches to another computer. So, the time to establish a USB link is reduced by
2
⁄3 of the time to just two seconds.
4.2 Increased Ability to Share
This change also improved the potential number of devices that can connect to any single TX unit.
The number was previously limited to 12 devices but is now limited to 12 different VID/PID identities.
This means you could have six keyboards and six mice all of the same make and model connected at one time and yet the TX unit
only sees one keyboard and one mouse.
4.3 Using Two USB Touchscreens—Enable Multiport Configuration
In some applications, you do not want USB devices to be merged but rather you want them to retain their individual identity, such
as when connecting two touchscreens to a single receiver unit.
The bottom two USB ports on the back of the receiver can be set not to merge. This feature is turned off by default (i.e., they
merge as standard) but can be turned on in the Web pages.
The feature is labeled in the USB settings tab as “Enable multiport configuration.”
It is currently not in the iPATH pages (Version 2.3) but will be in the next release.
4.4 Enable Isochronous Endpoint Attach
Some devices (for instance an iPhone
®
) have multiple USB devices reported and, in this case, one of the endpoints is isochronous.
Until Version 2.7, these combined devices would be rejected out of hand. Now the ServSwitch Agility still rejects the isochronous
part but allows the other USB features to proceed.
Isochronous devices are still not supported.
