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AR# 61797

Vivado Sysgen - The generated Accumulator block does not behave the same when implemented in DSP48s or within the Fabric


I have a design containing the Accumulator block in Sysgen.

My Sysgen simulations appear to work correctly but the design does not behave as expected on hardware.

It does not appear to come out of reset correctly.

Is this a known issue?


There is a known issue when using this block in Sysgen 2014.2. 

If this block is configured to use the "Fabric" implementation, then everything appears to work as expected.

However, if the implementation is changed to use the DSP48s on the device, incorrect behavior can be seen when running on hardware or when simulating the HDL Netlist project generated from the HDL Netlist compilation target.

A CR has been filed for this issue and it is under investigation.

The workaround at this time is to use the Fabric implementation.

AR# 61797
Date Created 08/15/2014
Last Updated 08/22/2014
Status Active
Type General Article
  • System Generator for DSP
  • Vivado Design Suite - 2014.2