In the same spirit as Brian Kerninghans chem preprocessor. I wrote a pic preprocessor in awk for drawing circuit diagrams. This is after looking for various options and did not find one for troff.
it can downloaded from http://plan9.bell-labs.com/sources/contrib/fernan/schem.tgz I have attached a sample output, showing a clone of an avr programmer i built. fernan
atmega8.pdf
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