Xschem is a schematic capture program, it allows creation of hierarchical representation of circuits with a top down approach . By focusing on interfaces, hierarchy and instance properties a complex system can be described in terms of simpler building blocks. A VHDL or Verilog or Spice netlist can be generated from the drawn schematic, allowing the simulation of the circuit. Key feature of the program is its drawing engine written in C and using directly the Xlib drawing primitives; this gives very good speed performance, even on very big circuits. The user interface is built with the Tcl-Tk toolkit, tcl is also the extension language used.

Features

• hierarchical schematic drawings, no limits on size
• any object in the schematic can have any sort of properties (generics in VHDL, parameters in Spice or Verilog)
  
• new Spice/Verilog primitives can be created, and the netlist format can be defined by the user
• tcl extension language allows the creation of scripts; any user command in the drawing window has an associated tcl comand
• VHDL / Verilog / Spice netlist, ready for simulation
• Behavioral VHDL / Verilog code can be embedded as one of the properties of the schematic block,
  

Xschem runs on UNIX systems with X11 and Tcl-Tk toolkit installed.

Documentation

Download Source code

Download Windows Binary

License

Software requirements:

- X11
- tcl-tk libs and developent files
- c99 compiler
- bison (only for compiling the grammar parser)
- flex (only for compiling the lexical analyzer
- Xpm library and -dev header files
- awk (tested with gawk and mawk)
- Linux debian / Redhat
- Solaris sparc
- Windows (with the cygwin layer and cygwin/Xorg X11 server, plus the tcl/tk toolkit and the -dev libraries)

Screenshots