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This version (06 Jun 2018 13:11) was approved by Alexandra.The Previously approved version (11 Aug 2017 15:47) is available.Diff

Scopy Logic Analyzer

General

To switch to this instrument click on the Logic Analyzer button from the left menu.

This instrument can run continuously, repeatedly triggering, by pressing the Run button or triggering once, by pressing the Single button.

The logic analyzer instrument consists of a channel manager, a central signal plot and a control panel for different settings.

Scopy Logic Analyzer


Channel manager configuration

The channel manager allows the user to enable or disable channels, set triggers, create groups of signals or set protocol decoders to groups. The groups can be created by selecting channels and pressing the button Scopy Group Channels or by dragging one channel/group over another channel/group. The drag and drop mechanism also allows the user to reorder the channels.

The channel manager can be collapsed by pressing the button Scopy Collapse Manager located above the plot.

Channel manager configuration for a pin:

Logic Analyzer Pin

  • Switch for enabling/disabling a channel.
  • Channel name.
  • Channel index.
  • Dropdown for trigger selection.
  • Check box for selecting a channel.

Channel manager configuration for a pin belonging to a group:

Logic Analyzer Pin in Group

  • Channel name.
  • Channel index.
  • Dropdown for decoder role selection.
  • Dropdown for trigger selection.
  • Orange delete mark for removing channel from group.

Channel manager configuration for a group:

Logic Analyzer Group

  • Switch for enabling/disabling a group.
  • Arrow button for collapsing/expanding the group.
  • Group name.
  • Dropdown for decoder selection.
  • Orange delete mark for removing the group
  • Check box for selecting the group.

The plot displays the signal data captured on the enabled channels and the decoded data for active groups.

The control panel can be opened by pressing the Trigger settings button, the General Settings button or the Channel Settings button. All the mentioned buttons are shown in the previous illustration.


General settings

Logic Analyzer General Settings

  • Time Base: – It can be changed either by pressing the +/- buttons or writing a value in the edit box. Pressing the center of the range circle toggles between fine/coarse modes.
  • Time Trigger Position: – It can be changed either by pressing the +/- buttons or writing a value in the edit box. Pressing the center of the range circle toggles between fine/coarse modes.
  • Repeated Mode: – Using the instrument in this mode consists of repeatedly waiting, acquiring and displaying one buffer at a time. However, when the time base is greater than 1 s/div, in order to avoid waiting too much for a buffer, the time trigger is moved on the leftmost position on the screen and the signals are plotted immediately, starting from the left side when an entire screen was plotted. In this situation, the user can also control the Frequency. If the time trigger position is modified, the instrument returns to the waiting mode, regardless of the time base value.
  • Stream Mode: – When the Stream mode is enabled, the time trigger is moved automatically to the leftmost position on the screen, the Frequency control is enabled, allowing the user to stream at any chosen frequency. In this mode, the signals are continuously drawn in the right side, not limited by one screen. If the time trigger position is modified, the instrument returns to the waiting mode, regardless of the time base value.
  • Frequency: – It can be changed either by pressing the +/- buttons or writing a value in the edit box. Pressing the center of the range circle toggles between fine/coarse modes. The maximum frequency is 3.03 MHz.
  • Export: – The Logic Analyzer can export current data in .csv (Comma-separated values) and .vcd (Value change dump) format. Using the “Export All” switch you can select and export data from all the available channels or you can create a custom selection using the dropdown. After deciding which channels should be exported, click “Export” and choose a file. The exported .csv files are compatible with instruments throughout the application, so you could load the file in the Pattern Generator.




Channel settings

If a channel is highlighted in the channel manager, the settings for that particular channel are displayed in this panel. All the channels/groups allow the user to change the name by writing a value in the edit box.

The buttons from the top right side of the panel allow navigation through the list of active channels, as shown in the following illustration. For groups, if a decoder is set, the required and optional roles for that decoder are displayed in this panel.



Use Cases


Prerequisites

  1. Connect ADALM2000 to your computer via USB.
  2. Start Scopy and connect to the device.
  3. From the left menu, choose the Logic Analyzer.


Enable & run multiple channels

  1. Disable 8 channels using the channel manager located in the left side of the plot. To disable a channel use .
  2. Use Hide inactive channels to hide the disabled channels. The plot will contain only the enabled channels.
  3. To acquire 1 s of data, change the time base to 100 ms, using the time base selector in the right menu. Open the right menu using the General Settings button.
  4. Start the acquisition using the “Run” button. After 1 s you should see 8 signals on the plot.


Create channel groups, decode & change UI elements

  1. Create a channel group with 3 channels.
    Use Select channel to select the channels.
    After selecting 3 channels, use the Group button to create a group
    Create channel group
  2. Setup a Parallel decoder for this group. Use the dropdown located in the right side of the group name to set a decoder.
    The roles for these 3 channels are automatically assigned for this decoder.
  3. Start the acquisition using the “Run” button. On the plot, above the 3 channels, the decoded information should appear as shown in the following illustration.
  4. Change the name of the existing group.
    Select the group. Open the right menu using the Channel Settings button.
    Use the mouse wheel to scroll until the Name text box is visible. Change the name of the group to “GROUP 1”.
  5. Create another channel group with 3 channels. (See step 1). Merge the two channel groups.
    To merge two channels group, use drag and drop. Select one channel group, and drag it inside the other channel group.
    You should have 5 channels in the first channel group (“GROUP1”) and the second channel group should stay the same.
  6. The roles for the remaining channels in GROUP1 should be automatically assigned. Observe the decoded value changing.
  7. Change signal color and thickness.
    Select GROUP1. Open the right menu using the Channel Settings button. Use the mouse wheel to scroll until the Thickness dropdown. Set the thickness to 3. This should change the thickness of every channel in the group.


Trigger Settings

  1. From the left menu, choose the Pattern Generator tool.
    Select channel 0 and create a group.
    Select the group and set the Clock pattern using the right menu.
    Do not start the Pattern Generator.
  2. From the left menu, choose the Logic Analyzer tool.
    Open the right menu using the General Settings button.
    Use the time base selector to set the time base at 1 ms.
    Use the time position selector to set the time position at 0 ms.
  3. Setup a trigger condition on channel 0, using the channel manager in the left side of the plot
  4. Press the “Single” button to acquire one buffer of data.
    The plot should remain the same, without any signals.
  5. Now Start the Pattern Generator using the left menu.
    The Pattern Generator generates a clock on the first channel, so the Logic Analyzer should trigger, and the signals should now be visible on the plot.


Interaction with Scopy Pattern Generator

  1. From the left menu, choose the Pattern Generator tool.
    Select channel 0 and create a group.
    Select the group and set the UART pattern using the right menu. Set the following parameters:
    1. baud: 115200
    2. data to send = “hello”.
  2. Start the Pattern Generator using the top right button.
  3. From the left menu, choose the Logic Analyzer.
    Create a group that contains channel 0. The group will be created at the bottom of the channel manager. Select the group and open the right menu using the Channel Settings button.
  4. Set the UART decoder to the group.
  5. Set the RX role to channel 0.
  6. Press the “Single” button to acquire just one buffer of data.
    Depending on the time base, the displayed data may change. At a time base of 500 μs/div, the result is the following.

    The decoded data is not visible, but using the “zoom” feature, you can check out specific areas of the plot.
    To zoom in, place the mouse over the plot and use the mouse wheel.
  7. Enable the cursors using the box on the left of the “Cursors” label. When the cursors are enabled, you can also enable/disable locking using the lock icon on the right of the “Cursors” label, as shown in the following illustration.
    Use the handles from the plot to move the cursors. Check their position and the measured signal using the cursor status below the channel manager.


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university/tools/m2k/scopy/logicanalyzer.txt · Last modified: 16 May 2018 15:35 by Alexandra