Internal flow ============= A (usually short) synthesis script controls Yosys. These scripts contain three types of commands: - **Frontends**, that read input files (usually Verilog); - **Passes**, that perform transformations on the design in memory; - **Backends**, that write the design in memory to a file (various formats are available: Verilog, BLIF, EDIF, SPICE, BTOR, . . .). .. toctree:: :maxdepth: 3 overview control_and_data verilog_frontend