The numeric part of the address contains the location. This location can have one
of two formats depending on the address type. The format nnnn is used for internal
memory locations. The format x.y is used for inputs and outputs where the first part
(x) identifies the module and the second part (y) identifies the input or output on
that module.
The parts of the address are numbered starting from zero and module zero refers to
the logic controller itself.