@Dcset - Don't Care Set
ABEL-HDL uses don't-care conditions to help in the optimization of
partially-specified logic functions. Partially specified logic functions are those that
have less than 2n significant input conditions, where n is the number of input signals. The @dcset option allows the optimization to
use 1 or 0 for don't cares to optimize these functions.
?= and ?:= Assignment Operators
CAUTION: The @dcset directive overrides Istype 'dc', 'neg' and 'pos' attributes.
See Also