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AR# 66009

2015.3 - Vivado - IOBUFE3 flag errors when SLEW attribute is set as a attribute in the HDL


When I try to set an IOB SLEW attribute, the 2015.3 Vivado tools error out:

[Synth 8-3438] module 'IOBUFE3' declared at '<path_to>/scripts/rt/data/unisim_comp.v:17551' does not have any parameter 'SLEW' used as named parameter override.


The SLEW attribute needs to be set in the XDC file, rather than the HDL code.

In Vivado 2015.3, the language template incorrectly contains this information in the IOBUFE3 instantiation template:

   IOBUFE3_inst : IOBUFE3
   generic map (
      SIM_INPUT_BUFFER_OFFSET => 0, -- Offset value for simulation (-50-50)
      SLEW => "SLOW" 

To resolve this issue, remove the parameter from the HDL instance and set the SLEW attribute in the XDC file.

AR# 66009
Date Created 11/18/2015
Last Updated 11/27/2015
Status Active
Type General Article
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