Epson LX-80, Operating Manual

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Us e App e ndix A to translate any character codes from h exa d ecimal
if the g u ide part of the line is not sufficiently helpful .
A h ex p ri n t out of a program shows you exactly what th e pr i n ter is
r eceivi n g, re gardless of what the computer is sending. The fo ll owing
test progra m lets you check to see what codes , if any , ar e p r oblems
for your co mputer system.
10 FOR X = 0 TO 255
20 L P R INT CHR$(X) ;
30 NF~ XT X
Put the pri nter in data dump mode and then RUN th e pr ogram .
Remember to pr ess th e ON LINE button to make the L X-80 print
the final line. Then c o mp a r e y our printout with the li s t of hex codes
in order in t h e middl e column s of page A-2 in Appendi x A . If any
are skipped or r e peated , y ou will know that your BASI C l anguage
changes some co de s b e for e it se nd s them to the print e r .
For examp l e, i n th e lin e b e low , which is the first line of [h e printout
of the test p rogram run on a QX-lO , you can s e e that in t hi s case
MBASIC c hange s hex 09 , w hich is the code for horizont a l tabbing ,
to several 20s, the c ode f o r a sp a ce. Ther e fore , y ou kn o w t h at if y ou
use this syste m , y ou mu s t be c a reful about sending a decim a l 9 (hex
09) .
T h e data d umping capability can help you debug a program qu ickl y .
Appendices A to C will help you translate the hex code s to ASCII
equivalents .
Coding Solutions
Once you ' ve d e t e rmined that a code creates problem s for your
printi n g, ei ther by trial and error or by using the data du mping
ca p a b i lit y of the LX-80 , you can start overcoming them .
B ecause eac h computer s y s tem deals with ASCII codes di fferentl y,
it is impossib l e to provide solutions for all potential problem s i n one
appendix. T he following g e neral approach s uggests possibl e way s to
h andle t h em.