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M1.3/M1.4 CPLD: Fitter incorrectly trimming pin from macro which is driving multiple outputs
Record #3055
Problem Title:
M1.3/M1.4 CPLD: Fitter incorrectly trimming pin from macro which is driving multiple outputs
Problem Description:
Urgency: Standard
General Description:
If you have multiple pins being driven by the same signal
inside a macro, and those pins in turn, drive output pins in
the top level schematic, the CPLD fitter will trim away all but
one net coming out of the macro. This is true for both
ABEL and VHDL macros.
Solution 1:
The current workaround for this issue is to have the signal drive multiple nets outside of the macro
instead of from inside
the macro.
In addition, add a buf to the signals which are being trimmed.
You would then have the macro pin going to a buf -> obuf -> opad
on the top level for the signal that was being trimmed.
End of Record #3055 - Last Modified: 12/07/99 10:48 |
