User Manual

Measuring
Measuring is possible only with a purchased license.
USB data signals (DATA+, DATA-) can be connected to any two inputs, other
inputs are allowed to be used for measuring of another signals or e.g. for
measuring of another USB communications. Measuring of more than only one
USB communication is possible.
Processing
When signals have been captured (= the test has been done) it is necessary to
decode it. It can take tens of seconds depending on amount of the captured
data. Decoding is proceed automatically, promptly when the data have been
captured, if it is enabled in the USB analyzer settings dialog or it can be launch
in the menu by choosing Decode → Decode Now! or hitting F9.
When decoding have finished there is a list of measured USB events in the
events window (which is simultaneously the main window).
Viewing
Consider that decoding have finished and list of measured USB events is in the
events window.
For decreasing number of events in the event window a configurable filter can
be applied so that only requested events are displayed. For that option open
the menu Settings Filter Settings. One or more USB addresses can be→
marked as requested such as 0,5..7 within range of 0 to 127 (USB uses 7bit
wide address range). The same principle applies to endpoints within range of 0
to 15 (the endpoint direction – bit 7 - does not matter).
The zero address is dedicated for devices without address set. Likewise the
zero endpoint is special control endpoint, which each device must include, the
only one that support bidirectional transactions.
Due to the fact that the USB specification does not allow single devices to send
data on they own the major part of the traffic is occupied by master (PC)
asking slaves if data has got ready.
Therefore it can be useful to mask that frames without any data (terminated
by NAK token), for doing that, as well as masking frames which is not destined
for any particular device(e.g. Start-Of-Frame token, Bus Reset), visit the menu
Settings Filter Settings.→
On the highest level there is possibility to display or hide transactions ended by
NAK token or ACK token, for that option use right mouse button and choose it
from menu.
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