code and the program will not work properly. The programs in this
manual do not use CHR$(9), but some do use its high-order version -
CHR$(137) - which your system will change to CHR$(9). In these
cases
use the following method to change your printer initialization
code to a number that is not used in the program. For example, you
can change your initialization code to one by typing:
PR#l
PRINT CHR$(9); CHR$(l)
TRS-80 solutions
A routine to POKE codes to the memory of a Model I is given
above. A special printer driver for either the Model I or the Model III
is also shown above. One of those methods should solve any prob-
lems with the programs in this manual.
IBM-PC solutions
There are two problems in using the IBM Personal Computer
BASIC to drive a printer. First, the IBM-PC BASIC inserts a carriage-
return/line-feed (CR-LF) after each 80 characters you send it. Second,
it adds an LF to each CR in an LPRINT statement.
Here is the way to adjust the width when it is the only problem. Tell
the computer that the print line is wider than 80 characters with this
WIDTH statement:
WIDTH "LPTl:", 255
The 255 is a special number that prevents the computer system from
inserting a CR-LF into the line. Unless, of course, there’s one in your
program.
The extra line feed-CHR$(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 "LPTl:" AS #l
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 #l, "Now I can print anything"
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