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The second approach is to use commercially available software that
is specifically designed to overcome these coding problems. Consult
your computer dealer or computer publications to see if a program
for your computer system is available.
The third approach consists of avoiding the software that is chang-
ing the codes. On most computers you can send each code directly to
the printer port. This bypasses the BASIC interpreter and avoids the
interface.
Unfortunately, this process is also different for each computer
system. Consult your computer’s manual to determine if you can
do the same on your system.
A fourth approach is to change the printer driver program in your
system. This requires a knowledge of machine language and of the
way your computer works. If you don’t have this knowledge, your
computer dealer may be able to help you or suggest someone who
can.
Solutions for Specific Systems
The next four subsections illustrate dealing with interface puzzles
on four types of computers.
Applesoft BASIC solutions
Applesoft BASIC does not use PRINT to send data to the screen
and LPRINT to send data to the printer as MBASIC does. Therefore,
put an
PR#l at the beginning of a program and change all instances
of LPRINT to PRINT.
If one of our programs contains an INPUT statement or a PRINT
statement, there will be a message that should go to the screen before
anything is sent to the printer. In these programs, leave the first lines
as they are and after the INPUT and/or PRINT statements, add a line
that states PR#l ; then change all the instances of LPRINT to PRINT
and put a line that states PR#0 at the end of the program.
Apple
®
II solutions
There are two types of problems that you who own Apple II
computers will need to address. The first is that the Apple II is an
8-bit computer, but its printer interface only handles seven bits. The
second is that there is one problem code number: nine.
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