Epson LX-80, Руководство по эксплуатации

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For exa m ple, o ne computer system handles form feeds b y itself . It
counts lines to k ee p track of the top of page . If a program sends the
ASCII code fo r f orm feed (1 2 ) to the printer , the comput er system
intercepts it a nd se nd s in s tead th e code for line feed (1 0) several
times. If you a r e in a graphic s mode with this system a nd send a 12
to fire pins 3 and 4 , th e computer system will intercept th at 12 and
send several lO s in s tead. Y ou can se e how this would ruin your
graphics. You w ould get pins 2 and 4 ( whose sum is 10) severa l times
instead of pins 3 and 4 onl y once .
If your comp ut e r sys tem r e moves or changes any code s sent to it ,
you can often d e sign around these problems by using oth e r n u mbers
with similar pa tt e rn s, and you can s ee Appendix F for a m ethod to
determine whic h c o des may ca use problems and for som e ideas on
overcoming t h os e probl e ms .