1 synthesis steps
1) Search Paths
rc:/> set_attribute lib_search_path path /
rc:/> set_attribute script_search_path path /
rc:/> set_attribute hdl_search_path path /
2) Target Technology Library
rc:/> set_attribute library lib_name.lib
- Target Library: Design Compiler uses the target library to build a circuit. During mapping, Design Compiler selects functionally correct gates from the target library. It also calculates the timing of the circuit, using the vendor-supplied timing data for these gates.
3) Loading the HDL Files
- sequentially: read_hdl file1.v read_hdl file2.v read_hdl file3.v
- simultaneously: read_hdl { file1.v file2.v file3.v }
read_hdl [-v1995 | -v2001 | -sv | -vhdl [-library library_name ] | -netlist] [-define macro=value ] ... file_list
4) Performing Elaboration
This is only required for top-level design. The elaborate command automatically elaborates the top-level design and all of its references.
5) Applying Constraints
- Operating conditions; clock waveforms; I/O timing
6) Applying Optimization Constraints
7) Performing Synthesis
rc:> synthesize -to_mapped
8) Analyzing the Synthesis Results
- generate a detailed area report, use report area
- generate a detailed gate selection and area report, use report gates
- generate a detailed timing report, including the worst critical path of the current design, use report timing
9) Exporting the Design
- gate-level netlist rc:/> write_hdl > design.v
- design constraints rc:/> write_script > constraints.g
- constraints in SDC format rc:/> write_sdc > constraints.sdc
10) Exiting RTL Compiler
quit or exit
2 recommended flow
#general setup #-------------- set_attributer lib_search_path ... set_attribute hdl_search_path .. #load the library #------------------------------ set_attribute library library_name #load and elaborate the design #------------------------------ read_hdl design.v elaborate #specify timing and design constraints #-------------------------------------- read_sdc sdc_file # add optimization constraints #---------------------------- ..... #synthesize the design #--------------------- synthesize -to_mapped #analyze design ------------------ report area report timing report gates #export design #------------- write_hdl > dessign.vm write_sdc > constraints.sdc write_script > constraints.g # export design for EDI #----------------------- write_design [-basename string ] [-gzip_files] [-tcf] [-encounter] [-hierarchical] [ design ]
3 working in the top-level(root) directory
Root is a special object that contains all other objects represented as a ‘tree’ underneath it.
The root object is always present in RTL Compiler and is represented by a “/”, as shown in above Figure.
Root attributes contain information about all loaded designs.