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Altera_Forum
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13 years ago

TimeQuest & source-synchronous center-aligned input

Hi, I need to constrain a source-synchronous center-aligned input and I've been reading some Altera documentation, as well as Rysc's guide. However I am still not sure if I am doing the right t...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

I've mainly done rgmii, which is DDR.

90 degrees centers the clock in the data eye for DDR, but 180 degrees does it for SDR. Be sure to look at the launch/latch edges for setup and hold make sure they make sense.