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AR# 55764

Vivado - 2013.x Vivado Synthesis -- RAM_STYLE attribute specified as Capital letters not working


When the RAM_STYLE attribute is specified in capital letters in RTL, Vivado Synthesis still infers a distributed RAM.


This issue was noted in -1 speed grade devices. 

Both RAM_STYLE=BLOCK and ram_style=block work with -2 speed grade devices.

However setting RAM_STYLE=BLOCK does not infer a block RAM in -1 speed grade devices, but instead infers a distributed RAM. 

Setting the ram style to block in lower case letters (ram_style = block) does infer a block RAM for -1 speed grade devices.

The issue is fixed in the 2013.2 release.

For prior versions, the workaround is to always specify the attribute in lower case (ram_style = block).

Linked Answer Records

Master Answer Records

Answer Number Answer Title Version Found Version Resolved
55334 2013.x Vivado Synthesis - Known Issues N/A N/A
AR# 55764
Date Created 04/28/2013
Last Updated 10/20/2014
Status Active
Type Known Issues
  • Artix-7
  • Artix-7Q
  • Kintex-7
  • More
  • Kintex-7Q
  • Virtex-7
  • Virtex-7Q
  • Less
  • Vivado Design Suite - 2013.1
  • Vivado Design Suite - 2012.4
  • Vivado Design Suite - 2012.3
  • More
  • Vivado Design Suite - 2012.2
  • Vivado Design Suite - 2012.1
  • Less