Answers Database
Foundation F1.x, Timing Simulator: Same bus name with different indices gives 'X' outputs
Record #3091
Product Family: Software
Product Line: Aldec
Product Part: Foundation Simulator
Problem Title:
Foundation F1.x, Timing Simulator: Same bus name with different indices gives 'X' outputs
Problem Description:
Urgency: Standard
General Description:
When a label is used for an input bus with one set of indices (eg 15:8) and an output bus with anoth
er set of indices (eg 7:0), the timing simulator does not distinguish between the two busses. The re
sult is X outputs for the input bus. Usually, the only signal that can be selected for simulation is
a bus of 15:0 as an output.
Solution 1:
For example, suppose a design contains an input bus called
MY_BUS[15:8] and an unrelated output bus called MY_BUS[7:0].
Although these are truly 2 separate and unique busses, they
will not be differentiated between in timing simulation. You
will only have the ability to select a bus called MY_BUS[15:0]
and this bus will be an output only.
Currently, the only solution for this problem is to name the 2
busses differently, ie MY_BUSA[15:8] and MY_BUSB[7:0].
End of Record #3091 - Last Modified: 03/03/99 11:32 |
