Epson SQ-2000, Руководство по эксплуатации

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After the entire figure is created in the array in memory it is
sent to the printer. Since we are using a 24-dot graphics option
the procedure is slightly complicated. The array in memory is
structured just as the figure will print: array element 0,0 is the
upper left corner, 1,0 is adjacent to it on the right, and 0,l is
directly below it. But when we print the array, we must send the
array elements in “stacks” of three. Each array element contains
one byte of graphics data, and to control 24 nozzles we must send
three bytes of data to the printer. Figure 6-10 shows the order in
which we must send the array elements to the printer.
First
print line
Second
print line
Third
print line
Additional
print lines
The bold italic numbers indicate the order that the
bytes of graphics data, contained in the array
elements, are sent to the printer.
Figure 6-10. Order of array elements
The printing routine starts in line 520. This program was writ-
ten on a Compaq computer, and this method of opening the
printer as a file avoids most problem codes with this computer.
Line 530 changes the line spacing to 24/180-inch so that there will
be no gaps in the printed design.
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