Teledyne LeCroy QPHY-USB3-Tx-Rx - Manual (Page 17)

QPHY-USB3-Tx-Rx Software Option
917719 Rev A
17
Oscilloscope and PeRT
3
With the addition of a PeRT
3
, the control of the P UT can also be automated. In the QualiPHY soft ware there are
corresponding “Scope PeRT3” configurations that can be selected. There are three for devices and three for
hosts: transmitter tests (TX), receiver tests (RX) and both TX and RX tests.
For TX testing the PeRT
3
can send an LFPS Ping to the PUT to cycle it through the different compliance patterns
CP0 – CP8. If the PUT does not support the LFPS Ping method of changing the compliance pattern and a
proprietary method must be used then the P eRT
3
should not be used for TX testing. Instead use the Oscilloscope
Only configuration as described above. Alternatively, if the PUT supports loopback the TX tests can be run using
PeRT
3
automation to place the PUT into loopback mode.
Note, that not all tests can be conducted correctly when using the loopback method. Therefore, the results should
be considered as informative and not used for compliance testing. In part icular, the de-emphasis test requires a
compliance pattern that does not have de-emphasis. In loopback mode the de-emphasis in the PUT cannot be
disabled so the de-emphasis measurement cannot be done properly. Furthermore, in loopback mode there are
usually skips present in the data that may cause variations in the results when compared to using the LFPS Ping
mode.
Oscilloscope and PeRT
3
with RF Switch
With the addition of an RF switch, QualiPHY can aut omate connection changes as well. As with the oscillosc ope
and PeRT
3 configuration, the QualiPHY software has three “Scope PeRT 3 RF Switch” configurations that can be
selected.
OPERATING THE PERT
3
MANUALLY
The PeRT
3
can be operated from the stand -alone PeRT
3
application or from within the XStreamDSO application.
For instructions on using the stand-alone application please consult the PeRT
3
doc umentation. In many situations
it is convenient to operate the PeRT
3
from within the XStreamDSO application. The PeRT
3
control dialog is
located under Analysis -> PeRT
3
. (The stand-alone PeRT
3
application must be installed in order for the PeRT
3
controls to appear on the Analysis menu.) When the dialog is first opened it looks as follows:
The first step is to setup the connection to the PeRT
3
server. Set the IP Address / Hostname control to the IP
address or hostname of the machine that is physically connected to the PeRT
3
via USB2 cable. The default value
is “localhost,” which is used when the PeRT 3
is connected to the oscilloscope. Next, click Connect to PeRT
Server to establish communication with the PeRT
3
. The text below the Connect to PeRT Server button should
change to indicate the connection is being established and shortly after it should indicate that the PeRT
3
is
connected. If the connection fails an error messag e is shown in the Stat us Message area at the bottom right of the
dialog. The connection fails if the PeRT
3
is already being accessed from the PeRT
3
stand-alone application or
from another oscilloscope or computer. After the connection is established a dial og tab is added for each PeRT
3
channel.
After the connection is established, set the Protocol, Data Rate, Clock Out and SSC cont rols as desired and click
Configure PeRT. After a brief delay the text below those cont rols indicates that the PeRT
3
is configured
successfully.
At this point the PeRT
3
is ready for use. Most of the controls on the PeRT
3
dialogs correspond closely with the
controls in the stand-alone application. One exception is the Output ALIGN/SKP checkbox. When this checkbox
is unchecked the PeRT
3
suppresses the symbols required to be ins erted periodically (SKP for USB3, ALIGN for
SATA, etc). The default state is checked; however, you may disable those symbols for transmitter testing in
loopback or for receiver test calibration.
The remainder of this section specifically focuses on using the PeRT
3
controls when testing USB3. The 3 key
operations are: LFPS Ping, Loopback and, receiver test calibration.