Bus Utilization View

Bus Utilization View displays both a Link Utilization and an Error Count over a specific time frame.

bus_utilization_view.png
Typical Bus Utilization View (Ports P1 and P6 Showing)

Bus Utilization Controls

  • Add Charts: Display Error Count or Link Utilization or both

  • Tile Vertical: Display windows vertically

  • Tile Horizontal: Display windows side-by-side

  • Synchronize Charts: Time frame is the same for both views

  • Delete Chart Setting: Delete display Error Count or Link Utilization or both

  • Zoom In: (Ctrl + mouse wheel

  • Zoom Out: Ctrl + mouse wheel

  • Fit to Screen: Full view of Trace

  • Show or Hide Ports: Show/Hide Port1 – Port8

bus_utilization_controls.png
Controls for Bus Utilization View (1)

Tools


Ports

Charts View

Close

Adjust Settings

Zoom In

Zoom Out

Fit to Screen

Select/Deselect all

bus_ut_chart.png

Show/Hide Ports by number


Note: Measurement Interval: The Measurement Interval parameter defines a sampling period for calculating graph data points. During each time interval, the graph will average all values within that interval and generate one data point for the graph.

  • Larger intervals will result in fewer data points, and thus less-precise graphs.

  • Smaller intervals will result in more data points, and thus more-precise graphs.

  • Graphs, such as Link Utilization, are usually best-served by larger intervals of >100ms.

  • The RTT graph requires high precision and is best served by a minimum interval of 1ns.

att_5_for_550207502.jpeg
Measurement Interval = 10,000 nsec
att_6_for_550207502.jpeg
Measurement Interval: 10,000 nsec (Fewer Samples)
att_7_for_550207502.jpeg
Example – Measurement Interval = 10 nsec
att_8_for_550207502.jpeg
Measurement Interval – 10 nsec (Many Samples)

Tile Horizontally

att_9_for_550207502.jpeg
Bus Utilization Windows – Tiled Horizontally

Adjust Settings

You can Adjust Settings of the Display window. In this case the background color is Blue and the Port Numbers are listed below the Display.

adjust_settings.png
Adjust Settings – Error Count Display > Updated, Link Utilization > Defaults

You can also change from a line chart to an Area chart and change the Measurement Interval.

adjust_settings_area_chart.png
Adjust Settings – Link Utilization > Area Chart, Measurement Interval = 20 nsec

Rolling Cursor Over Point in Display

To find out information about a specific point in the display, roll your cursor over the point of interest and its value will be displayed.

rolling_cursor.png
Rolling Cursor Over Specific Point on Waveform – Value Displayed

Zoom In Using Cursor

Another way to use the Zoom function is to move your cursor into the display panel, hold down the left mouse button and drag it over a section of the display. When you release the mouse the highlighted section will be displayed over the entire width of the display.

att_10_for_550207502.jpeg
Data of Interest – Compressed, No Details
att_11_for_550207502.jpeg
Cursor – Click and Drag over Area of Interest (710 usec to 713 usec)

Highlighted area only displayed below.

att_12_for_550207502.jpeg
Details from 710 usec to 713 usec Displayed

Display Bus Utilization and Spreadsheet Views

If you open the Spreadsheet View and the Bus Utilization View, clicking on an item in the Spreadsheet View will highlight that item in the Bus Utilization Charts. Initially, you’ll see the entire Trace in the Bus Utilization View.

att_13_for_550207502.jpeg
Bus Utilization and Spreadsheet Views – Near 628 usec
bus_zoomed.png
Bus Utilization (Zoomed In) and Spreadsheet Views – Near 628 usec

Quick Navigation

One other way that the Spreadsheet View and Bus Utilization View work together, is that if you have zoomed in enough to see individual events, you can click the left mouse button on an edge to view the Item Number(s) that contribute to the Utilization number in the graph.

quick_nav.png
Spreadsheet and Link Utilization (Items Averaged)