Epson FX-100 User Manual download pdf (Page 198)

below picks off any potential problem codes and changes them to less

dangerous numbers.

210 IF F>8 AND F<14 THEN F=F-5

This line takes any number between 8 and

and subtracts 5 from it,

putting it out of the trouble range. Adjust this test to fit your system.

You may see another problem with the figure. The standard 7-dot

line spacing may be off just enough to add a slight gap every seven

rows. An easy fix for this is to adjust the line spacing as needed with

the CHR$(27)“3" command. This gives you the ability to make

adjustments as fine as one-third of a dot. For example, in this program

you can set a 6-2/3-dot line spacing by changing line

to:

70 LPRINT CHR$(27)"3"CHR$(20)CHR$(7);

Higher resolution

If everything did go according to plan, your printed figure resem-

bles a circle of radius

dots, but the resolution isn’t all that you might

hope for. For one thing, the individual dots are clearly visible. To

make a more continuous figure, you need

graphics mode of higher

density. To get it, change line 130 to:

130 LPRINT CHR$(27)"*"CHR$(1)CHR$(N)CHR$(0);

This does give a more satisfactory density, but now the program

distorts the circle. Mathematically inclined folks can adjust for this

distortion by creating an ellipse in the array (the horizontal compres-

sion creates a circle). If you pursue this course, keep in mind that the

FX has several graphics densities available.

With figures this small, it is difficult to obtain a smooth curve. The

solution is to draw larger circles.

Unfortunately, larger arrays gobble up memory. For example, an

array wide enough to stretch clear across an g-inch page in Single-

Density would contain over 200,000 cells (480 x 480). Considering

that each cell takes up at least two bytes, there is not much hope of

tucking the entire array into memory all at once.

So how can you squeeze more print out of your arrays? For non-

symmetric designs, you are pretty well stuck with the memory limita-

tion of two bytes per cell unless you are willing to resort to more

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Epson FX-100 User Manual Page 198