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AR# 52986

2012.3 Vivado - Value of IDELAY_TYPE dropped when transforming Virtex-6 IODELAYE1 to Kintex-7 IDELAYE2 primitive


When transforming or funneling from a Virtex-6 IODELAYE1 primitive to a Kintex-7 IDELAYE2 primitive, the value of IDELAY_TYPE is being dropped.

The Virtex-6 IODELAYE1 primitive has a property named IDELAY_TYPE which has value of "VAR_LOADABLE".

The Kintex-7 IDELAYE2 primitive also has a property named IDELAY_TYPE but "VAR_LOADABLE" is not a legal value.

The value in Kintex-7 should be "VAR_LOAD" or "VAR_LOAD_PIPE".


When synthesizing a design with a Virtex-6 IODELAYE1 primitive instantiated with IDELAY_TYPE set to "VAR_LOADABLE", Vivado is dropping the IDELAY_TYPE during the transform to the Kintex-7 IDELAYE2. 

This leads to a CRITICAL WARNING when trying to open the Synthesized Design in Vivado.

This issue has been resolved in Vivado Design Suite 2012.4.

AR# 52986
Date 05/20/2014
Status Active
Type Known Issues
  • Vivado Design Suite - 2012.3