i.CanDrawIt® is optimized for drawing schematic diagrams with logic symbols, but also supports PLC style ladder logic diagrams. The diagrams are allowed to be free form, but function blocks can easily be placed in order to appear the way a traditional ladder logic diagram would. The following is a simple example. The symbols or function blocks used to create ladder logic are found in the Ladder library.
There are a couple of special considerations required for creating ladder logic diagrams that can translate into code using i.CanDrawIt. (1) Individual line symbols must be used to create the power rails. If you want the symbols to appear as a single contiguous rail, use the annotation polygon tool to add the graphic touches. (2) The special WIRE OR symbols must be used when combining two signal sources. The ordinary wire junction can be used to split a single signal source out to multiple destinations (junction on right in above example). However, the WIRE OR must be explicitly used to bring two signal sources together to a single destination (junction on left in above example). This is because the wire-or function needs to generate code to do the logical or-ing of the two source signals. You can use the tool options to cause function block names to not be shown if you do not like the "WIRE_OR" showing on your drawing. Simply click on any function block to bring up its options dialog, and change "Show" from yes to no.
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