Questa*- Intel® FPGA Edition Simulation User Guide

ID 730191
Date 4/23/2025
Public
Document Table of Contents

3.8.1. Post-Synthesis and Post-Fit Netlists for Simulation

During compilation, the Quartus® Prime Compiler first synthesizes the design into a netlist (a set of module instances interconnected by wires) of low-level device family specific ATOM blocks. This is also known as technology mapping. ATOMs are logical representations of various Altera® FPGA hardware blocks, such as lookup tables, DSPs, and memory blocks. The netlist that results from Quartus® Prime synthesis is the post-synthesis netlist. Refer to Quartus Prime Simulation Library.

In the next stage of Quartus® Prime compilation, the Fitter takes the post-synthesis netlist as input, and produces a place and route solution for the ATOMs in the target FPGA that you specify. The netlist that results from place & route is the post-fit netlist.

The Quartus® Prime software can generate post-synthesis and post-fit netlists for simulation in Verilog HDL or VHDL format as Step 1: Generate Gate-Level Netlists for Simulation describes. Generally, The post-fit netlist has associated routing and cell (that is, ATOM) delays. However, the Quartus® Prime software does not support simulating a post-fit netlist with timing delays. In other words, the Quartus® Prime software supports post-fit functional simulation, but does not support post-fit timing simulation.