Epson SQ-2550 User Manual

For example, if you wish to send 1632 columns of graphics data,

nl should be 96 and n2 should be 6 because 1632 = 96 + 6 

256.

The printer will interpret the number of bytes determined by nl

and n2 as graphics data, no matter what codes they are. This

means that you must be sure to supply enough bytes of

graphics data or the printer will stop and wait for more data

and will seem to be locked. If, on the other hand, you supply

too much graphics data, the excess will be interpreted and

printed as regular text.

This first program is just a simple example to show you how

the graphics command, column reservation numbers, and data

can be used in a BASIC program.
Type in and run the following program; be especially careful to

include both semicolons. The program produces the printout

you see below it.

10 WIDTH "LPT1:",255

20 LPRINT CHR$(27)"*"CHR$(32)CHR$
30 FOR X=1 TO 120

40 LPRINT CHR$(170);

50 

NEXT X

(40)CHR$

(0) ;

Line 20 selects single-density 24-element graphics mode 32 and

also reserves 40 columns for graphics. Since 24-element

graphics requires three bytes of data for each column, line 30

begins a loop to supply 120 bytes of data. Line 40 contains the

number 170, which produces the first element pattern shown in

the section on nozzle labels, and line 50 finishes the loop.

Software and Graphics 4-15