Lattice Diamond: How can I block clock transfers in the timing analysis tool?
A clock domain transfer or crossing occurs when one register in a data path is clocked by CLKA and one register by CLKB.
To block this transfer from the timing analysis use the preference:
BLOCK INTERCLOCKDOMAIN
If you are looking to relax or analyze this path use the preference:
MULTICYCLE FROM CLKNET "CLKA" TO CLKNET "CLKB" 2 X ;
For more information and a complete description on these preferences refer to the ispLEVER Online Help