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Altera_Forum's avatar
Altera_Forum
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13 years ago

TimeQuest and Timing constrataints, what to we enter for tsu, th, tco, tpd

When we are constraining a design we can enter values for the tsu, th, tco, and tpd as well as the clock itself.

My question is that, for a given design how do I know what tsu, th, tco I should be entering? I mean are these values not intrinsic to the device itself? What value would I enter for these and why can we also ignore them?

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

    tsu, th, tco constraints are usually specified for IO pins. These values will depend on the protocol/device data sheet that you are interfacing with.

    There is no need to specify tsu, th for internal data paths as they will be taken care of by Quartus tool depending on your target device.