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Receiver definition
module receiver_module( RST, BtoR_REQ, DO(0..31) )( RtoB_ACK )
{
var RtoB_ACK : boolean;
/* The usual way we would approach writing the environment
would be along the lines of:
assign
next(RtoB_ACK) := case
RST : 0;
BtoR_REQ : 1;
!BtoR_REQ : 0;
else : RtoB_ACK;
esac;
(Specifying when a signal changes.)
However, notice that here we never get to the "else"
case. In fact, we can write a simpler environment:
*/
assign
init(RtoB_ACK) := 0;
next(RtoB_ACK) := case
RST : 0;
else : BtoR_REQ; /* RtoB_ACK must be asserted a cycle after
the assertion of BtoR_REQ and deasserted
a cycle after the deassertion of BtoR_REQ.
This unusually simple specification was
made to keep this tutorial simple. */
esac;
}
%for i in 0..1 do
instance receiver_%{i} : receiver_module( RST, BtoR_REQ(%{i}), DO(0..31) )
( RtoB_ACK( %{i}) );
%end
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