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VRb's avatar
VRb
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7 years ago

In Signal Tap, I have set trigger conditions on more than one signal(tapping on AXI signals). I have set to Basic AND condition on 2 signals while rest of them are don't care . Can I expect a capture correctly?

I have set Allow trigger condition changes only which will allow me to change trigger condition changes after compilation.

Since I want to change the trigger condition dynamically, I am confused with the BASIC AND and Don't care options. Can anyone help me with this?

3 Replies

  • VRb's avatar
    VRb
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    Hi Anand,

    I have gone through the links. The video does not give a explanation of Basic AND and don't care combination.

    Also, the video every time has Allow all changes in the signal tap. When this option, is set we have to recompile the entire design every time we change the control on the trigger condition.

    To avoid this, we have to select the option, Allow trigger condition changes only. This allows us to change the trigger condition control at any time. This doesn't require compilation unless you bring in a new signal to tap.

    I will try this out as I don't have a clear picture now and post the findings.

  • VRb's avatar
    VRb
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    I have tried it and this option works.

    When choosing multiple signals to tap, we can set it to Allow trigger condition changes and most of the signals don't care. This will allow us to capture based on any of the trigger condition. This can be changed once the compilation is complete.

    My example;Signal tap on AXI signals

    I selected valid and ready of all channels as trigger condition. Also, since I know both valid and ready should be high for AXI transfer, I selected BASIC AND operation. During tapping i choose which set of valid and ready I want to capture.