Side-By-Side Characters - Epson FX Series User Manual

Very nice. Using two characters side by side provides a larger matrix
and therefore gives more flexibility in character design. But there is
one problem. When two user-defined characters are placed side by
side, there is one intermediate column that, unless the first character is
printed in Emphasized Mode, cannot contain any dots. As you can see
in Figure that is the shared intermediate column.
16-1,
Unused
columns
Figure 16-1. Side-by-side characters
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