The Fan-In Control tool has the following limitations:
The Fan-In Control tool has been designed to be a slave to the primary core definition screen. Therefore, you should define exceptions to default values only after you have made all primary screen selections. Changing the main screen may affect the defined fan-in values. Information on modified fan-in will be provided in the Report window and should always be verified for correctness.
The ability to perform no buffering on some control signals is limited to a single polarity because of hardware limitations. For example, ACT 2, ACT 3, 3200DX, MX, SX, SX-A, and eX limit asynchronous clears to Active Low only. Choosing Active High for this signal causes the No Buffering option to be unavailable. When this situation occurs, go back to the primary screen and change the active level for the given signal if no buffering is a must.
Some control signals, such as the Count Enable signal are not included in the Fan-In Control tool because fan-out is corrected internally using AND and OR logic functions.
Use the Fan-In Control dialog box to specify Auto Buffering or No Buffering, Max Load, and Signal Width.