Reading the Signal Display

Control signal changes are displayed in a graphical format. On the left side of the screen is a list of the signals currently being displayed, and to the right of each name is a line displaying the state of the signal over time. A single line means that the signal was logically off, while a double line means that the signal was logically on. Dotted lines are used for signals that were not present at the time of capture. For example, if you are monitoring a circuit that does not use CD, that line appears as a dotted line in the control signal display.

The four information lines at the bottom of the window tell you what events are being shown in the window, and where you are in relation to the buffer as a whole.

  • Current Snapshot: The first line tells you what event numbers are in the current snapshot, the total number of events, and the amount of time that passed between the first event in the snapshot and the last event (called Delta).
  • Current Visible: The second line gives the same information about the events that are currently visible in the window. Because you can zoom in and out, often the events being shown in the window are not the same as the number of events in the current snapshot.
  • Currently Selected: The third line gives the same information for the currently selected events. You can highlight a range of events by clicking at any point on the graphical display and dragging the mouse to the left or the right. The third line shows information for the selected range.
  • Selected Time: The fourth and last line shows the exact timestamps of the first and last bytes in the currently selected range. Note that this does not tell you the timestamp for the entire snapshot or the events displayed in the window, just the highlighted events.   The raw timestamp value is the number of 100-nanosecond intervals since the beginning of January 1, 1601. This is standard Windows time.

A single mouse click places the cursor in the window. The analyzer highlights all six signal changes in one color, and uses a different color to specify the control signal line clicked on. You can highlight a range by clicking and dragging the mouse to the right or left. You can also use the arrow keys to move the cursor to the right or left.

The Signal Display window is synchronized with other windows in the analyzer. A range highlighted in the Signal Display window is also highlighted in the Event Display and Frame Display windows.

The Snap to Nearest Change icon lets you place the cursor on the signal change you want to look at without needing to click on exactly the right spot. Find the line corresponding to the control signal you want to look at. Click on the line, and the analyzer moves the cursor to the nearest change. If you highlight a range, the analyzer "snaps to" the nearest changes on either side. This feature is active when the Snap To button is pressed, and inactive when the button is not pressed.

Use the Zoom In and Zoom Out buttons to increase and decrease the magnification of the window. The analyzer changes the magnification by a factor of 2, 4 or 8, depending on the option selected in the Signals menu.

If you want to see a range in greater detail, highlight the range you want to view and click on the Zoom to Selection icon . The analyzer zooms in to show only that range in the window. If the range is small, the analyzer may add additional events to fill up the window. To view the entire snapshot in the window, click on the Display Entire Buffer icon .

Note that if you bring up the Signal Display window while data is being captured, the window shows you the state of the control signals at the time the window was opened. To update the display, use the New Snapshot icon .

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