pcb-rnd knowledge pool

Abstract: XSCHEM is a small, independent schematics editor implemented in C, tcl, awk, running on X11. Because of VLSI, it has strong support for hierarchy. Recently it got support for slotting and exporting tEDAx netlists, making XSCHEM suitable for drawing the schematics for a layout done with pcb-rnd. This tutorial demonstrates a simple XSCHEM-to-pcb-rnd forward annotation.

  Download and compile XSCHEM . The installation process is somewhat non-standard, and it is also possible to run XSCHEM from source, without installation; please refer to the installation section in README.TXT for more details.

First draw the schematics using XSCHEM.

Then set the netlist output format to tEDAx: options menu, tEDAx netlist.

Then click on the Netlist button to get a tEDAx file written. If the file name of the schematics is nand, the result will be written as nand.tdx

In pcb-rnd, open the file menu, import, then select the submenu for importing schematics from tEDAx:

After selecting the file, the netlist is loaded and all footprints are placed. The process from this point is the same as with any other import: disperse your subcircuits and optimize the rats nets with the key sequence {c r}.

The import step can be done from the command line using the LoadTedaxFrom() action.

See also:

• similar workflows for LTSpice, TinyCAD, Mentor Graphics, KiCad's eeschema
• how to automate forward annotation e.g. using Makefiles