Epson LX-86, Руководство пользователя

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A hex printout of a program shows you exactly what the printer is
receiving, regardless of what the computer is sending. The following
test program lets you check to see what codes, if any, are problems
for your computer system.
10 FOR X=0 TO 255
20 LPRINT CHR$(X) ;
30 NEXT X
Put the printer in data dump mode and then RUN the program.
Remember to press the ON LINE button to make the Lx-86 print
the final line. Then compare your printout with the list of hex codes
in order in the middle columns of page A-2 in Appendix A. If any are
skipped or repeated, you will know that your BASIC language
changes some codes
before it sends them to the printer.
For example, in the line below, which is the first line of the
printout of the test program run on a system that changes hex 09,
which is the code for horizontal tabbing, to several 20s, the code
for a space. Therefore, you know that if you use this system, you
must be careful about sending a decimal 9 (hex
09).
The data dumping capability can help
you solve problems
quickly. Appendix A will help you translate the hex codes to
ASCII equivalents.
Coding Solutions
Once you’ve determined that a code creates problems for your
printing, either by trial and error or by using the data dumping
capability of the LX-86, you can start overcoming them.
Because each computer system deals with ASCII codes differently,
it is impossible to provide solutions for all potential problems in one
appendix. We can, however, point out generic problems and suggest
ways to handle them.
There are four common approaches. First, you may be able to buy
an alternative printer interface card for your system. This is the best
solution for 7-bit system problems. See your computer dealer for
advice about this.
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