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Altera_Forum's avatar
Altera_Forum
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12 years ago

Can we specify cut timing path along with the code?

Hello, I have a toggle synchronizer like below and want to exclude the domain crossing register transfer ce_t1 <= ce_toggle from timing analysis. Is there any way to do it automatically, e.g. b...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

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This what I found in the QII13.0 help:

Wouldn't you need an extra register stage before applying the xor to get the output pulse?

Regards,

Josy

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Yes Josy I will drive xor only after two stages as the signals are assumed synchronised from that node onwards.

FvM approach is one stage and is sampling to xor from first synchroniser register. This will fail more frequently than two stage.

Since you found the cut path attribute then it means it exists and hopefully still active.