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AR# 12242

4.1i Modular Design - "FATAL_ERROR:Place:xvkapfastfitter.c:971:1.28 - TBUFSET containing TBUF..."


Keywords: TBUF, BUFT, 3-state, tristate, buffer, active

Urgency: Hot

General Description:
During active implementation of a module, PAR reports the following error:

"FATAL_ERROR:Place:xvkapfastfitter.c:971:1.28 - TBUFSET containing TBUF
ADIO<15>/PSEUDO_TBUF is partially placed."


This is a known issue that occurs when multiple 3-state buffers (TBUFs) drive the same net, but are part of different modules. Modular Design does not currently allow this configuration. TBUFs driving the same net must ALL be part of the top level/context logic, or part of the SAME module.

The following figure illustrates the correct and incorrect configurations:
Using 3-State Buffers (TBUF) in Modular Design
Using 3-State Buffers (TBUF) in Modular Design
AR# 12242
Date 08/11/2003
Status Archive
Type General Article