User's Manual

Print head
Decimal sum
of the desired
pin pattern
Figure 10-4. Pin combinations
Now that you, know the labels for the pins, how would you fire the top
pin? Why, by sending LPRINT CHR$(128), of course. And how about
the bottom graphics pin? That’s right, LPRINT CHR$(l). If you
wanted to fire only the top and bottom pins, you’d simply add 128
and one, then send LPRINT CHR$(129). By adding the appropriate
label numbers together, you can fire any combination of pins you
want.
Now you can see why not being able to send an ASCII code above
127 is the same as not being able to fire the top pin.
First Graphics Programs
The next few exercises show you what you can do by printing with
one pin per column. That may sound simple, but with one pin at a
time you can create interesting figures; you move from a straight line
to a slash, a large caret, a wave pattern, and finally to a diamond
pattern.
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