Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

  • State Resolved
  • Locked Locked
  • Replies 5 replies
  • Subscribers 53 subscribers
  • Views 4767 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Draw graph in realtime CCS

Simon Jagla
Expert 7865 points
Other Parts Discussed in Thread: TMS320F28035

Hi,

In the graph tool properties (CCS5.5) I can choose a “Sampling rate in Hz”. I thought it would increase the update speed of the values but it does not change anything. What is it good for?

Is it possible to draw a graph in realtime with the graph tool. The customer asks about how to draw a graph of a variable that gests updated with 18kHz. I will tell him to buffer the samples in the device and read out the buffer afterwards but I’m also curious if it is possible e.g. with a XDS560 trace emulator to read out single values with this speed and draw it. Is this possible with the graph tool?

  • 0
    TI__Guru**** 440091 points

    Hi Simon,

    Simon Jagla said:
    In the graph tool properties (CCS5.5) I can choose a “Sampling rate in Hz”. I thought it would increase the update speed of the values but it does not change anything. What is it good for?

    As described in the CCS Help:

    This field contains the sampling frequency for acquisition buffer samples, such as for analog to digital conversion. The sampling rate is used to calculate the time and frequency values displayed on the graph.

    For a time domain graph, this field calculates the values for the time axis. The axis is labeled from 0 to (Display Data Size * 1/Sampling Rate).

    For a frequency domain graph (FFT Magnitude, Complex FFT, FFT Magnitude and Phase), this field contains the number of samples (rounded down to the nearest power of 2) used for the FFT frequency analysis. The graph displays the frequency contents of the signal in the range from 0 to Sampling Rate/2

    Simon Jagla said:
    Is it possible to draw a graph in realtime with the graph tool. The customer asks about how to draw a graph of a variable that gests updated with 18kHz. I will tell him to buffer the samples in the device and read out the buffer afterwards but I’m also curious if it is possible e.g. with a XDS560 trace emulator to read out single values with this speed and draw it. Is this possible with the graph tool?

    What device is the customer using?

    Thanks

    ki

  • 0 in reply to Ki
    TI__Expert 7865 points

    Sorry, I see I could have found this information on my own.

     

    The customer uses C2000 (TMS320F28035) devices. At the moment he uses the C2000 XDS510LC USB emulator but I did not find a hint that it has capabilities to speed up the update rate of the graph tool.

  • 0 in reply to Simon Jagla
    TI__Guru**** 440091 points

    the default refresh rate of the views is 500ms. He can adjust this value in the workspace properties. I think it is capped at 100ms but I'm not sure (they can try lower).

  • 0 in reply to Ki
    TI__Expert 7865 points

    Thank you very much for this information.

    As far as I can see this 100ms seems to be a limitation of CCS and not of the emulator or device. Do you know if the xds560 has the capability to read out variables with higher speed and visualize them?

  • 0 in reply to Simon Jagla
    TI__Guru**** 440091 points

    If I remember correctly, the limitation is indeed of CCS... specifically at quicker refresh rates, it starts to have a negative impact on CCS performance.

    Simon Jagla said:
    Do you know if the xds560 has the capability to read out variables with higher speed and visualize them?

    Using a faster emulator will not help here since the refresh rate is fixed to CCS and not the emulator.