Black Box Dual 2.7 and iPATH 2.3, ServSwitch Dual 2.7 and iPATH 2.3 Chapter 4: USB-Related Issues

Chapter 4: USB-Related Issues

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 R X

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.

This change also improved the potential number of devices that can connec t 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.

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 b e in the next release.

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 Serv Switch Agility still rejects the isochronous

part but allows the other USB features to proceed.

Isochronous devices are still not supported.