Commodore MPS 1200 - Saving Character Designs In the MPS 1200 s Memory

Copying Standard Characters
BASIC
Hex
chr$(27) ":" chr$(O) chr$(O) chr$(O)
1B 3A 00 00 00
Many users of user-defined characters don't define an entire alpha-
bet; instead
they define only a few special characters that they need
for
their specific applications. Because of the way the MPS 1200
stores character designs,
it's easy to combine standard and user-
defined characters in
your printouts.
The standard characters are all stored in the MPS 1200's ROM
(Read Only Memory). Each time your computer sends an ASCII
code
to the printer, the MPS 1200 prints the character. User defined
characters are
stored in a different area of the MPS 1200's memory
(it is called RAM, for Random Access Memory), but are accessed
in the
same way. You are, in effect, temporarily replacing the MPS
1200's standard characters with your newly designed characters
(without losing the standard characters).
When you turn the MPS 1200 on or reset it with the ESC @
(master reset) command, the user-defined RAM is empty: there are
no character definitions. Therefore, if you want to design a few
special characters to
be used with the standard alphabet, you can
start
by copying all of the standard characters from MPS 1200's
ROM to RAM with the ESC: chr$(O) chr$(O) chr$(O) command.
Then you can use both your own newly created characters with the
standard characters. You'll see how injust a minute.
Saving Character Designs
In the MPS 1200's Memory
BASIC
chr$(27) "&" chr$(O) chr$(n1) chr$(n2)
chr$(a) chr$(dO) . .. chr$(d10)
Hex
1 B 26 00 n1 h n2h ah dOh d10h
After you've designed a character on a paper grid, the next step is to
send
that character definition (or group of definitions) to the MPS
1200 so that the characters can be printed. Doing this requires the
MPS 1200's most complicated command (but it's really not so bad
after you've tried it a few times).
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