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Bells and Whistles
Here's the result:
Try changing to 72 X 72 DPI resolution - change line 10 to
LPRINT CHR$(28)
- and compare the printout:
NOTES: When the printer is in graphic mode, any ASCII code sent to the
printer will be printed as a column of dots. Many computers automatically
send a Carriage Return and a Line Feed code after the 80th or 132nd code
number; these would be printed as dot patterns. Check your computer manual
to find out how to override this feature. (The most common method is a
WIDTH statement.)
If you want to print the pattern represented by CHR$(3), enter it twice in your
program, like this:
CHR$(3);CHR$(3)
Multiline Graphics
Up until now, we've been sticking to single-line images
;
after
exiting graphic mode at the end of the line, the computer in-
serts a Carriage Return code, which tells the printer to print
the line, and a Line Feed code, which advances the
paper.
But you can print more than one line of graphic data without
returning to the normal ("text") mode. All you need are
these special Line Feed codes:
ETX SO
CHR$(3);CHR$(14)
03 OE (hex)
-
Graphic Line Feed with
Carriage Return: prints the
line, advances paper 7 /72"
and returns printhead to
left margin.
ETX DC4
CHR$(3);CHR$(20)
0314(hex)
-Graphic Line Feed without
Carriage Return: prints the
line, advances paper 7 /72"
but does not return print-
head to left margin
Why a 7
/
72" line feed? Because a line of graphic printing is
7 /72" high, so a normal line feed (1 /6" or 1 /8") would leave
a gap between
lines.
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