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AR# 7680

Foundation 4.1i simulation - "Bus Conflict" errors occur during the simulation of a multiplexer with 3-stated buffers in Foundation


Keywords: FNDTN, LogiBLOX, Foundation, functional simulation

Urgency: Standard

General Description:
When I perform a functional simulation in Foundation with a design containing multiplexors that use 3-state buffers or LogiBLOX-generated multiplexers, a window pops up during simulation that is titled "Bus Conflicts".


This is a known issue with the Foundation logic simulator, and the warning message that is generated can be safely ignored.

When a LogiBLOX mux is generated with more than four inputs, the default is to implement the mux using 3-state buffers. The simulator has difficulty interpreting the buffers and generates the "Bus Conflicts" error.

You can simply ignore the warnings that pop up, and click on "Cancel".

However, for timing simulation, you should examine the source of conflict and the duration.
AR# 7680
Date Created 09/16/1999
Last Updated 08/12/2003
Status Archive
Type General Article