Telestra USB Connections Matrix (Ver. 1, Rev. D.3)
4
Copyright © 2008 Advanced Simulation Technology inc.
Power-On Ordering Requirements and Lost USB Devices
The USB audio distribution architecture has speci
fi
c requirements regarding the power on
sequencing of devices in order to achieve a working system. The Telestra processor system must
perform a discovery process in order to
fi
nd all the devices that are connected, and hence this sys-
tem is started last in the sequence of elements. The discovery process runs as part of the system
framework boot process, or it is manually initiated from RMS, by clicking the “Hardware” tab,
and then the “Reset USB network” link. Prior to this all other elements of the USB sub-system
must be connected, and powered on.
Note
that the Prism/Spectrum extender architecture should
be powered on before or simultaneously with the Iris audio interface units.
If any element of the USB sub-system is powered off and then back on again without rebooting
the Telestra processor, or initiating a manual USB discovery, then the result will be that those
devices are “lost” to the system, and will no longer process audio. The most effective way to
check for this condition is to look at the RMS system, select the “Hardware” tab, and then the
“Layout” tab. Any Iris units that were connected at the time of system boot and have been subse-
quently powered off will show up with a red ‘X’ through the device. If pro
fi
ling is turned on (see
Telestra 3 User Guide for details), then any device that is not active on the USB sub-system will
be reported with a red ‘X’. To recover from this situation, power on the required USB devices
(Prism devices
fi
rst, Iris devices last), and then either reboot the Telestra, or initiate a manual USB
re-discovery using RMS. If using RMS, once the re-discovery process has completed, it will be
necessary to reload the model.