[ABANDONED] High Speed Sampling Bandwidth

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  • Hello,

    Thank you for your inquiry.
    The 1 kHz value is not the maximum value but a guaranteed value for one specific setup. You should see a footnote at that value explaining how it came to be.
    In theory sampling rates >10 kHz are achievable for a single variable.

    Embedded wrote:

    Is this a hardware limitation ?
    It is generally a target device limitation.
    See here segger.com/products/debug-prob…nk/models/model-overview/
    (Even though J-Trace PRO should also show Unlimited* as the J-Link PRO model. Website will be updated accordingly.)
    We can guarantee a sampling frequency of 1 kHz for 1 variable with 1 MHz interface speed.
    If you try to sample multiple variables you definitely need to increase the target interface speed to keep 1 kHz sampling frequency for each variable.
    Our high end probes support up to 50 MHz target interface speed. However this does not mean your target device will work that fast. So again the most likely bottleneck will be the target device and not the debug probe.

    Instead of HSS RTT could be used. The benefit would be that we work with a on target buffer here and can transfer larger data blocks at once which in theory will yield in a larger data throughput:
    segger.com/products/debug-prob…about-real-time-transfer/
    With RTT you can reach a data transfer rate of ~2 MB/s. The drawback would be that code would need to be executed on the target device which could impact your real time behaviour slightly.

    Best regards,
    Nino
    Please read the forum rules before posting.

    Keep in mind, this is *not* a support forum.
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  • Hallo Nino,
    thank you for the detailed description.
    I use Segger Scope V6.11m with a J-Trace PRO for Cortex-M and get this 1kHz limitation message(see picture).
    So i can ignore this message ?

    Thank you,
    Embedded
    Images
    • jlink trace.jpg

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