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Altera_Forum's avatar
Altera_Forum
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18 years ago

question about set_input_delay

The following list describes the options for the set_input_delay command, anybody tell me when shall we specify the -rise|-fall option? -clock <clock name> Specifies the source clock. -clock...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

You could have different rise/fall times outside the part. For example, you could have an external -max -rise of 3.0ns and -max -fall of 2.9ns, or something like that. To be honest, I've seen a lot of complex constraints and have still never used these options.