The Build System

The build system employed in this project is based on vbom or "VHDL bill of material" files which list for each vhdl source file the libraries and sources for the instantiated components, the later via their vbom, and last but not least the name of the vhdl source file. All file names are relative to the current directory (see for example the vbom's of sys_w11a_n2 and tb_w11a_n2 ). A recursive traversal through all vbom's gives for each VHDL module all sources needed to compile it. The vbomconv script in tools/bin does this, and generates, depending on options,

The Makefile's in general just contain a few definitions and includes (see Makefile for sys_w11a_n2 and tb_w11a_n2). Two master Makefiles contain pattern rules for simulation and synthesis and encapsulate all the vbomconf magic (see generic_ghdl.mk and generic_xflow.mk). A full w11a system with USB support is build from about 100 vhdl source files, test benches from about 120 vhdl source files. Using the vbom's a large number of designs can be easily maintained.