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AR# 2583

PAR 1.4: ERROR: x52ap:111 5200 Design uses to many TBUF's or BUFT's


Keywords: PAR, Error:x52ap, BUFT, TBUF, Longline, Maximum,
Three state signals, 5200.

Urgency: Standard

Description: Here is a typical error message:

ERROR:x52ap:111 - This design contains 64 three-state (TBUF) output signals. However, the target device can only accommodate a maximum of 60 three-state signals. Please either reduce the number of three-state signals in your design accordingly, or retarget your design to a larger XC5200 device.

This can be seen when you move a design that used to place and route in XACT, but when moved to M1 issues the error.

This is the result of a software change. In a 5200 CLB there are 4 Logic Cells. Each of these Logic Cells can drive a BUFT which in turn drives a Longline. In Xact the software would allow you to use all 4 of these BUFT's. However, M1 only allows you drive 3 of the 4.


If the design uses more than 75% of the BUFT's you will need to modify the design or move to a larger part.

If the design uses less than 75% of the BUFT's the error is the result of user constraining to many BUFT's to a certain row or column. The user will need to adjust his constraints accordingly.

This will be fixed in M1.5.
AR# 2583
Date Created 08/31/2007
Last Updated 10/20/2008
Status Archive
Type General Article