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AR# 38368

Spartan-6 FPGA MCB - Why are the RZQ and ZIO pins swapped when migrating from MIG v3.4 to v3.5?


In MIGv3.5 and later version, the default RZQ and ZIO pins are swapped from previous releases.

If I change the pins back to the MIGv3.4 recommendations or change to other pins LOC options, MIG will show the warning: "The selected design's timing has not been verified with non-default RZQ/ZIO locations".

What is needed to ensure timing is met?


PIN locations from all versions satisfy the MIG requirements for RZQ and ZIO pins.

MIG v3.5 and later version pin recommendation have shown to give better results in terms of timing margin and SI simulation.

It is recommended to use the new pin locations.

However, as long as timing is met and the pin requirements for RZQ and ZIO are satisfied, the pins can be moved.

Version History:
9/4/2014 - Initial Release

Linked Answer Records

Associated Answer Records

Answer Number Answer Title Version Found Version Resolved
34055 MIG Spartan-6 FPGA MCB - What are the requirements for the RZQ and ZIO pins? N/A N/A
AR# 38368
Date Created 09/30/2010
Last Updated 09/04/2014
Status Active
Type General Article
  • Spartan-6 LX
  • Spartan-6 LXT
  • ISE Design Suite
  • MIG