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IBM PC BASIC solutions
There are three problems in using the IBM Personal Computer
BASIC to drive a printer. First, the IBM PC BASIC inserts a carriage-
return/line-feed (CR-LINE FEED) after each 80 characters you send it.
Second, it adds an LINE FEED to each CR in an LPRINT statement.
Third, it will not send hex 1A (decimal 26).
Here is the way to adjust the width when it is the only problem. Tell
the computer that the print line is wider than 80 characters with this
WIDTH statement:
WIDTH "LPT1:",255
The 255 is a special number that prevents the computer system from
inserting a CR-LINE FEED into the line. Unless, of course, there's one
in your program.
The extra line feed—CHR$(10)—that accompanies each carriage
return—CHR$(13)—is no problem except when you need to use
CHR$(13) in a graphics program. Getting rid of the extra CHR$(10) is
rather complicated. First you open the printer as a random file:
OPEN "LPT1:" AS #1
Although this allows you to send any code to the printer, you can no
longer use the LPRINT command. Instead, you must use a PRINT #l
command:
PRINT #1, "Now I can print anything"
This does allow you to print anything, but it ignores any previous
WIDTH statements.
If you want to print more than 80 columns per line in a graphics
program, you must therefore change your opening statement to
include the appropriate WIDTH statement:
OPEN "LPT1:" AS #1 : WIDTH #1, 255
And for the programs in this manual, don't forget to use PRINT #l
instead of LPRINT.
There is no easy solution to the problem with CHR$(26). It is best to
change any instance of decimal 26 (hex 1A) in your programs to
another number.
C-7
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