Epson LQ-510 User Manual page 111

Notice that the dots overlap quite a bit. This design was printed
using the triple-density, 24-pin graphics option because the density
is the same (180 dots per inch) in both directions.
Adding the following lines to the preceding program causes the
pattern to print 10 times in a row as shown below:
15 FOR C=l TO 10: RESTORE
65 NEXT C
Software and Graphics
Graphics
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