Epson FX High-Speed Double-DensityGraphics Mode, 11-1), 7 WIDTH LPRINT, 20 A$=CHR$(27)+"*"+CHR$(2)+CHR$(50)+CHR$(0), SINGLE-DENSITYGRAPHICS

SINGLE-DENSITY GRAPHICS

The printer fires pins 1, 3, 5, and 7 (with the respective exponential values of 1, 4, 16, and 64) in the first column and pins 2, 4, and 6 (exponential values 2, 8, and 32) in the second. And it alternates that sequence for 50 columns-50 columns in Single-Density.

This program also mixes graphics and text on one line. It does that by using semicolons to keep both kinds of output on the same print line.

High-Speed Double-Density Graphics Mode

Now let’s print the same pattern in twice the normal (Single) den- sity. Change the first 0 in line 20 to a 2 and retype the text in line 50 as shown below:

20 A$=CHR$(27)+"*"+CHR$(2)+CHR$(50)+CHR$(0)50 LPRINT " HIGH-SPEED DOUBLE-DENSITY GRAPHICS ";

If your computer system requires a WIDTH statement to prevent the printer from issuing a carriage return before the graphics line is com- plete, add it now:

7 WIDTH LPRINT 255

The format for this statement may be different for your BASIC; see your software documentation.

HIGH-SPEED DOUBLE-DENSITY GRAPHICS

The program still prints 50 columns of dots, but now it presses them together and prints them in half the space. They print at the same speed as in Single-Density Graphics.

This High-Speed Double-Density Graphics Mode has one draw- back. Because the dots are so closely packed, two dots in the same row cannot appear in two consecutive columns. In the above program we avoided the problem by never calling up one dot twice in succession. If you try to print two consecutive dots, the printer simply ignores the second one (see Figure 11-1).

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