Sharp PC-1500 Instruction Manual page 93

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F.5. GPR INT
The GPRINir statement provides direct, programmable control over the dots of the display
w indo\v. Since the GP RINT statemen t sets and resets dots i.•i1ithin any 7·dot column.
it
is normally
used in conjunction with the GCU RSOR instruction. The GCURSOR statement selects 1he
appropriate column for modification and the GPRINT statement manipulates the dots o.•1ithin
that colurnn. T he GPRINT statement is also capable of pr'inting seve ral contiguous columns of
in formation in a single st;atcmcn t.
In orde r to understand the format of the ()PRINT statement. it is necessary to unders tand
hO\" J the dots w ith in a column arc con tro11ed . The pattern of energized do1s within a column
may be specified t!ither as a decimal nunlber o,. as a hexadecin,al
character str ing.
If
the decimal
system is used, then P.ach rO\V may be visualiied as being numbered, from t he top down, by a
Po1o\ler of t\Vt>. T his is illustrated belo'<v;
1 - - - - - - - -
2 ·- - - - - - - -
4 - - - - - - - -
8 - - - - - - - -
16 - - - - - - - -
32-- - - - - - -
64---- - - - -
With 7 dots to a column, each of which may either be on or o ff, the1e are 128 possible dot
patterns. Thus, to specify a particular pattern one uses the format :
GPRINT pattern-expression : pauern·expression2 . . {etc) ..
where:
pattern -expression evaluates to a number in 1he iange 0 10 127 and speci fics the patt ern of
energized (lots. Several pattern expressions may optionally be specified
and must
be separated by either a sem icolon or a comma. If a comma is used, a blank column
\\lill be left bet\\leen every printed co lumn,
Let
us illustrate
the utility of the GPA INT instruction by creating a new chllractcr: an Up
Arro\v. First.
we
design our character
on a
grid representing
the
rows and columns:
1
--- - * -- --
2
-- * - * - *--
4
*--- *- --·
8 - - - - · - - - -
16 - - - -
* - - - -
32 - - - -
* - - - -
64 - - - - · - - - -
2 3 4 5
r caution
Observe the following when correcting the PRINT command in a program tor a GPRINT
command:
Example: r Rewite "PR INT" enui rely into "GPRIN T".
20
PiilNT
AS
L1 nse rti ng only "G" does not allow the computer to judge it as "GPRINT".
{Th is is regarded as "G" an d " PR I NT".)
The same can apply when the CURSOR command is corrected to a GCURSOR command, or
to the printer commands.
91
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