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AR# 64364

Vivado Synthesis - How to debug multi-driven nets "Critical Warning:[Synth 8-3352]"?


How do I debug multi-driven nets which are reported by Vivado Synthesis as follows:

CRITICAL WARNING: [Synth 8-3352] multi-driven net tx with 1st driver pin '<1st pin name>' [<filename of 1st pin>:<line number>]
CRITICAL WARNING: [Synth 8-3352] multi-driven net tx with 2nd driver pin '<2nd pin name>' [<filename of 2nd pin>:<line number>]


You can try to debug using the HDL code mentioned by the message and try to find the conflicting drivers on that signal.

However, when the drivers are at different hierarchical levels in a complex and large design, it is much easier to use the elaborated netlist.

For a design in project-mode, the elaborated netlist can be opened from the GUI by selecting "RTL Analysis -> Open Elaborated Design".

In non-project mode, use the synth_design -rtl option.

Once the RTL netlist is loaded, create a schematic with the pins mentioned in the message and track down all drivers of the connected net.

AR# 64364
Date 05/25/2015
Status Active
Type General Article
  • Vivado Design Suite