Epson LX-80, Руководство по эксплуатации

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To see how more than one line combines to form a figure, enter a n d
r un th e following program, which uses two of the lines you h ave
a lr ea d y t y p e d and adds several more.
1 0 L PR I N T CHR$(27)"1";
20 F OR R ~ ~ l TO 3
30 L P RINT CHR$(27) "K"CHR$(100)CHR$(0);
1 1 0 F OR X= l TO 50: LPRINT CHR$(135)CHR$ (42);
50 NEXT X: LPRINT
6 0 LPIUNT CHR$(27) "K"CHR$( 100)CHR$(0);
70 FOR )(: :: 1 TO
flO:
LPRINT CHR$(42)CHH$ (85);
80 NE X T X: LPRINT: NEXT R
90 L l 'HIN T CHR$(27)
"@ "
N ow run th e program to see the six print lines combine int o a
p a tt e rn :
T h e s hort a nd simple program that produced the pattern dem ons-
t r a t es m a n y e lements of graphics programming. In order to p oint
t h ese o u t it i s necessary to break the program down into step s.
Lin e 1 0 c h a n g es to a 7-dot line spacing, which is the height of th e dot
p a t te rn s u sed in the program , thereby removing the space b e t ween
th e p r in t lin es.
Lin e 2 0 b e gins a loop to produce multiple print lines . Lines 30 and
4 0 a r e th e sa me as above , but an LPRINT is added to line 5 0 to
p ro du ce a lin e feed after line 40. Lines 60 and 70 are like line s 3 0 and
40 exce p t th at line 70 uses a reversal of the patterns in line 40 . As the
l oo p i s exe cuted , the program prints lines 40 and 70 alternat e l y so
that the p a tt e rns of the print lines will fit together well .
N o t ice th at th e graphics command can be in effect for only one p rint
li n e. T h e co mmand is in lines 30 and 60 so that it is issued each ti me
a n ew p r int line is begun. You cannot print more than one lin e of
g r a phic s with o ut having the graphics command issued each tim e.