This package permit the creation of simple ladder diagram into TeX documents.
The code must be inserted between en tikzpicture section.
Add the packages : \usepackage{tikz} \usepackage{ladder}
All contacts and relays are, by default, added in series
\ladderLinebegin a new ladder net\startParallelbegin a parallel segment\setParallelbegin the new parallel segment\unsetParallelend of the parallel segment
\ladderNO[type]{name}{mnemonic}a Normally Opened contact\ladderNC[type]{name}{mnemonic}a Normaly Closed contact Type may be P (rising edge), N (falling edge)...
\ladderc[type]{name}{mnemonic}a relay Type may be R (reset), S (set)...