Epson MX-80 User Manual page 28

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Chapter 9

Trouble at the Old Corral?

Oh-oh. Now what did we do? You might know, just when things were going

so well. Looks pretty cute tho, doesn't it?

Remember, whenever any "switch" is thrown by sending a Code, (except

DOUBLE WIDTH), it stays thrown until reversed back to normal. In this case,

Code 15 was sent, and all characters became COMPRESSED (132 CPL). It

takes a Code 18 to switch it back to NORMAL (80 CPL). (Everybody gallop

back to Appendix B again. We'll know it well before we're done.)

The compression principle also applies to the TABs. If we are printing 132

characters per line, then the width of each TAB must also be compressed

compared to the normal 80 CPL. That's why the first 2 lines are shifted to the

left. Everything is working quite normally. (What WOULD you do if you

wanted to align the first 2 print lines with the 3rd?)

(Sure — change the TAB values in lines 10 and 20. Not now, tho. We're busy.)

Never Look Back — It Might Be Gaining

Line 40 might be the toughest, but it's not bad if we hang in there. It obvious-

ly consists of one LPRINT statement, one TAB, two character strings, and

one STRING-string. The STRING$( 18,21 1), in case you forgot, prints the

ASCII character 21118 times in a row. Everybody back to the ASCII chart in

Appendix G to see what 211 stands for.

Users with computers which do not have the STRINGS feature may

substitute a FOR-NEXT loop system to do the same thing.

Line 40 can be placed with:

40 LPRINTTAB ( 3 6) CHR$ ( 1 9 8) ;

FOR N = 1 TO 1 8

4 4

L P R I N T C H R $ ( 2 1 1 ) ;

NEXT N

4 8

L P R I N T C H R $ ( 1 8 5 )

c *

Hmm. Very interesting. The graphics set is the same as the TRS-80 uses, but

the ASCII numbers are all increased by +32. Hmmm — some more. (We'll

have plenty of time to explore that whole situation in Chapter 4.)