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Registered: ‎11-04-2010

Questa FIFO simulation model broken for one-bit-wide FIFO

This post is potentially related to: https://forums.xilinx.com/t5/Simulation-and-Verification/Fifo-generator-v13-2-3-out-is-always-X/td-p/977487

Mon Jan 13 2020

This README.txt is part of a ZIP file with these contents:

1. README.txt: this file
2. fifo_one_bit_ex.tcl: project creation script
3. original_sources: directory containing sources


1. Use a shell with Vivado 2019.1 and Questa 10.7c in the $PATH.
2. Edit fifo_one_bit_ex.tcl and change line 119 to point to your Questa 10.7c compiled simulation libraries.
3. vivado -mode batch -source fifo_one_bit_ex.tcl
4. Open fifo_one_bit_ex/fifo_one_bit_ex.xpr
5. Run the simulation, note that it FAILS
6. Change the simulation settings to use the Vivado simulator
7. Run the simulation, note that it PASSES
8. Create a service request to fix the Questa version of the FIFO behavioral model

The Questa simulation model is broken for one bit wide FIFOs.