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Altera_Forum
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13 years ago

how to start a multicycle process correctly

hi, i would do a large bit subtractor with a multicycle process to relax setup timing. when i receive new data to be subtracted(A ,B), i store them in 2 registers clocked @ 100MHz. Once i have ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

In short, you the user design the multicycle and insert constraints. With enable based constraint you are asking to deconstraint all enabled registers. Your enable is both en_reg ANDed with start_sub_process. deconstraints are defined in terms of registers, not processes.