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Altera_Forum
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17 years ago

Create SDC constraint file for a bi-direction bus

This is a question about how to constraint a bi-direction bus relative to a single input clock. I have a 8-bit bi-direction bus that is clocked by a single input clock. In input direction the min ...
Altera_Forum's avatar
Altera_Forum
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17 years ago

See the Quartus handbook, Volume 3, Section II, Chapter 7, Table 7-4.

For tsu and tco, "latch - launch" in the table is the 20 ns period for your case. That means the set_input_delay -max and set_output_delay -max are each 20 - 4 = 16 ns.

For th and min tco, "latch - launch" is zero for your case. Note the minus sign that makes set_output_delay -min be -1.0 ns.