Which means that the layout tools can now perform
synthesis as well.
The popular languages used to write a netlist are:
An example verilog netlist can be downloaded .
RTL style of coding
The gatelevel netlist from the synthesis tool is taken and imported into place and route tool in Verilog netlist format. All the gates and flip-flops are placed; clock tree synthesis and reset is routed. After this each block is routed. The P&R tool output is a GDS file, used by foundry for fabricating the ASIC. Backend team normally dumps out SPEF (standard parasitic exchange format) /RSPF (reduced parasitic exchange format)/DSPF (detailed parasitic exchange format) from layout tools like ASTRO to the frontend team, who then use the read_parasitic command in tools like Prime Time to write out SDF (standard delay format) for gate level simulation purposes.
Physical design: from RTL/Netlist to GDS2 - …
Synthesis is the process in which synthesis tools like design compiler or Synplify take RTL in Verilog or VHDL, target technology, and constrains as input and maps the RTL to target technology primitives. Synthesis tool, after mapping the RTL to gates, also do the minimal amount of timing analysis to see if the mapped design is meeting the timing requirements. (Important thing to note is, synthesis tools are not aware of wire delays, they only know of gate delays). After the synthesis there are a couple of things that are normally done before passing the netlist to backend (Place and Route)
What is a GATE level netlist in Verilog coding
Choose options "All" and "Extract FSM" and click OK. Thisperforms initial mapping of the RTL to a netlist. This will take some time based onthe design size. This step can be considered as a coarse level synthesis. Toperform more fine grained synthesis and optimize the design, we setup operatingconditions and constraints to meet various goals such as performance, area andpower. After performing a generic build on the design, you can view the designusing the "Schematic" tab of the BG interface. There will not bea picture of the aes_cipher_top cell, but you can see the structure of thesmaller building block cells by selecting them in the menu under the "logical"tab at left.
Design Compiler: RTL Synthesis - Synopsys
The netlist is then supposed to perform the same function as thecorresponding
The netlist out of the synthesis tool is then fed into layout tools toproduce
the layout of the chip.
Physical design (electronics) - Wikipedia
At this point we have synthesized our originalVerilog design, which was implemented on theRTL level into a gate-level design. We also verified that the synthesis resultis still correct by using our original testbench.
Now your GUI window should show a netlist on the right side ..
It is not necessary to rewrite the RTL description as submodules can be grouped together during synthesis. This allows for different optimization settings, i.e. high speed parts can be synthesized with very stringent timing constraints while non critical parts should consume the least amount of resources (area) possible.
this is the end of the Logic Synthesis Tutorial
This automatic process is carried outby
what are called synthesis tools, which are softwares available frommajor
EDA vendors like Synopsys, Cadence or Mentor Graphics.