You may switch between character sets at any time-even in the middle of a line. To try it, place semicolons at the end of lines 80 and 100 in the program above.

Copying ROM characters to RAM

After running the program above, if you select the user-defined character set and try to print other characters, the only one that will print is the arrow. Since no other characters are in the printer’s user-defined RAM area, nothing else prints. Other characters don’t even print as spaces; it’s as if they were not sent at all.

In many cases, you may want to redefine only a few of the characters to suit your needs; the rest of the alphabet will work fine as it is. As you have seen, it is possible to switch back and forth between the normal character set and the user-defined character set. It is, however, rather inconvenient.

To make things easier, your printer has a command that allows you to copy all of the standard characters from ROM to the user-defined character set.

The command format is as follows, where the value of n represents the font family:

ESC : 0 n 0

Note: This command cancels any user-defined characters you have created. You must send this command to the printer before you define characters.

If you use this command at the beginning of a program, then define your special characters and select the user-defined character set, you can print with the user-defined set as your normal character set. You never need to switch back and forth between sets.

Letter Quality characters

If you select Letter Quality printing with the ESC xl command, you can design user-defined characters using up to 29 columns of the Letter Quality/Proportional grid. The dot columns are spaced closer together

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Using Software and Graphics