User-Defined Characters; User-Define D Characters; Designing Your Characters - Epson LQ-2550 User Manual

If you change one of the 8-pin graphics options to a 24-pin graphics
option without changing the program that supplies the graphics data,
you will print garbage (if the program prints at all). Remember, the
24-pin graphics options require three times as much graphics data as the
8-pin graphics options.

User-Defined Characters

With this printer, it is possible to define and print characters of your own
design. You can design an entirely new alphabet or typeface, create
characters for special applications such as mathematical or scientific
symbols, or create graphic patterns with user-defined characters to serve
as building blocks for larger designs.
Below you can see samples of typefaces created with the user-defined
character function.
You can make the task of defining characters easier by using a
commercial software program that either assists you in creating
characters or simply supplies you with sets of characters already created.
Also, some popular commercial software programs take advantage of
the printer's user-defined character function to enhance printouts. (These
characters are called download characters in some programs.)
Standard characters are stored in the printer's Read Only Memory
(ROM), and user-defined characters are stored in the printer's Random
Access Memory (RAM).

Designing your characters

User-defined characters are like dot graphics because you send the printer
precise instructions on where you want each dot printed. In fact, planning a
user-defined character is like planning a small dot graphics pattern.
Using Software and Graphics 4-23