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Altera_Forum's avatar
Altera_Forum
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13 years ago

What is the number mean in bar of SignalTap II logic analyzer?

When we watch the waveforms in ST logic analyzer, there is a bar at the top of waveform, there are numbers in it. It does not looks like time since no unit. What is it? I guess it should be sampling clock number, then multiple with sampling clock period (we know it since we configure it in STP file), then we can know the time, right?

Another question I have is about Trigger enable. If we want to watch 20 signals, if we enable trigger for all the pins, then we can set different trigger condition for each signals we want to watch. If we disable all the signals just left one enable, then logic analyzer will record all the signals when that signal's (we set trigger enable) trigger condition meets, right?

This approach seems be more similar as the logic analyzer equipment we use.

Thanks.

6 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    Hi,

    the numbers are the sampling clock numbers, you can change this with cursor "above" this bar, right mouse click and change from sample number to time units (a window will appear to enter the sampling clock).

    For the trigger condition: If you set more than one trigger, than all conditions must be met and with the last condition being true the trigger activates. Best on trigger options is to look into the Help (search for trigger condition) as there are many options to choose from...

    Best Regards
  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    --- Quote Start ---

    Hi,

    the numbers are the sampling clock numbers, you can change this with cursor "above" this bar, right mouse click and change from sample number to time units (a window will appear to enter the sampling clock).

    For the trigger condition: If you set more than one trigger, than all conditions must be met and with the last condition being true the trigger activates. Best on trigger options is to look into the Help (search for trigger condition) as there are many options to choose from...

    Best Regards

    --- Quote End ---

    Thanks, you mentioned "all conditions must be met", these conditions don't need to be meet at same time, right?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    Hi,

    no they do not need to be met same time, the trigger will activate when all conditions are (sequentially) met. If you define e.g. two conditions, the one aims the trigger and the other activates.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    --- Quote Start ---

    Hi,

    no they do not need to be met same time, the trigger will activate when all conditions are (sequentially) met. If you define e.g. two conditions, the one aims the trigger and the other activates.

    --- Quote End ---

    Thanks. And the it also does not care the sequence of trigger condition, right?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    Exactly...

    If you need sequences you have to go with advanced trigger functions rather defining conditions only..

    Regards
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    --- Quote Start ---

    Exactly...

    If you need sequences you have to go with advanced trigger functions rather defining conditions only..

    Regards

    --- Quote End ---

    Thanks very much!