mirror of git://sigrok.org/pulseview
116 lines
4.9 KiB
Plaintext
116 lines
4.9 KiB
Plaintext
== Data Analysis
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Once you have acquired some measurement data, it's time to have a look and see what
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insights you can gain from it. Usually, the first step is to look at the data as a
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whole, achieved by clicking the _Zoom to Fit_ button:
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image::pv_analysis.png[]
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<1> Zoom-to-Fit button
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<2> Zoom in/zoom out buttons
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<3> Cursors
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<4> Time scale (used to set up and show markers, see below)
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If you have located an area of interest (maybe with the help of decoders, more about
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that later), you can zoom in on it using the _zoom in_/_zoom out_ buttons, using the
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scroll wheel of your mouse or the pinch/expand gestures on your touch panel.
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[NOTE]
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When a data capture is ongoing, the Zoom-to-Fit button stays active if you click it,
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meaning that PulseView automatically fits all data to the views until either the
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capture is finished or the Zoom-to-Fit button is clicked again.
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If you want this feature but don't want to always have to click the button, you
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can enable the "Always Zoom-to-Fit" option in the settings.
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=== Cursors and Markers
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Just looking at the signal data however is usually not sufficient. A lot of times,
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you'll want to make sure that timings are honored and the bit times are like what
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you'd expect. To do so, you'll want to use cursors and markers.
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In the picture above, you can enable the cursor by clicking on the cursor button.
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You can move both of its boundaries around by clicking on the blue flags in the
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time scale area. The area between the two boundary lines shows the time distance,
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its inverse (i.e. the frequency) and/or the number of samples encompassed. If there's
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not enough space to see these, you can either zoom in until it shows, hover the mouse
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cursor over the label in the middle or right-click on the label to configure what
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you want to see. You can also move both boundaries at the same time by dragging said
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label.
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image::pv_cursors_markers.png[]
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<1> Cursors button, showing enabled state
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<2> Cursor
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<3> Marker
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Markers are movable indicators that you can create wherever you like on the
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time scale - just double-click on it and it'll create one for you where your
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mouse cursor is at the time, or use the context menu when right-clicking on
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the ruler or a signal trace.
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You can click on its label and you'll have the option to change its name, or
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drag it to reposition it.
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When you have multiple markers, you can have PulseView show you the time difference
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between the markers by hovering over one of them, like so:
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image::pv_marker_deltas.png[]
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This works on the cursor, too.
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Speaking of which - if you want to place or move the cursor ranges quickly, you
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can also press '1' and '2' on your keyboard to attach either side to your mouse
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cursor. They will stay put when you either press Esc or click with the left
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mouse button. This also works when the cursor isn't even showing, so using this
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method allows you to place the cursor quickly without having to enable it first.
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[NOTE]
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For timing comparison purposes, you can also enable a vertical marker line that
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follows your mouse cursor: _Settings_ -> _Views_ -> _Highlight mouse cursor_
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[NOTE]
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There is also a special kind of marker that appears for each time the data
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acquisition device has triggered. It cannot be moved and appears as a vertical
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dashed blue line.
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=== Special-Purpose Decoders
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There are some decoders available that analyze the data instead of decoding it.
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You can make use of them to examine various properties of the signals that are
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of interest to you.
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Among them are:
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* Counter - counts pulses and/or groups of pulses (i.e. words)
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* Guess bitrate - guesses the bitrate when using a serial protocol
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* Jitter - determines the jitter (variance) of a signal
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* Timing - shows the time passing between the chosen signal edges
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=== Other Features
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==== Signal Label Area Resizing
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Trace Views also allow you to maximize the viewing area by minimizing the area
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occupied by the label area on the left. To do this, simply position the mouse
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cursor at the right edge of the label area (or left edge of the viewing area).
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Your mouse cursor will change shape and you now can drag the border.
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This way, you can give signals long, expressive names without clogging up the
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view area.
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==== Multiple Views
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You can create multiple views by clicking on the "New View" button on the very
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left of the toolbar. These can be rearranged as you wish.
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==== Session Saving/Restoring
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When closing PulseView, it automatically saves the sessions you currently have
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open, including the signal configuration and any protocol decoders you might
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have added. The next time you start it again, it'll be restored to its
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previous state.
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This metadata is also saved with every .sr file you save so that the next time
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you open the .sr file, your signal configurations, views and decoders are
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restored. These metadata files have the ending .pvs (PulseView Setup) and can
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be edited in any text editor if you wish to change something manually.
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Additionally, you can save or load this metadata at any time using the
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save/load buttons.
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