Required Signals

System Generator automatically adds the following ports for you if there is at least one synchronous element in the task. If your processing is purely asynchronous you can add a register on the validwords signal to force system generator to implement these ports.

Port ce_clr is not added by System Generator.  You should add an input gateway to your model called 'ce_clr' to ensure this signal is present on the interface on the core created by System Generator.