Downloadable and Custom Commands
Descenders
Earlier in this chapter we mentioned the descender informa- tion. When we left it as azero you probably thought this was easy. Well, it is! We only have two choices for descender data; it’s either a zero or a one. When it’s a zero, nothing happens. When it is a one, all the dots that make up our character are shifted down two rows. Why do we want to perform this magic? If you look at the lowercase g in magic, you can see that the tail of the g drops down below the bottom of other characters. This is a descender. Let’s take our copyright symbol example and define the @ symbol as we did before and make the “&”symbol our copyright symbol with a descender (shifted down two rows).
!O | REl4 | brfinc the Ercaoe character |
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20 | ESC$=CHRS(??! |
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24 | REtl COW c5aractwsto RAM |
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i5 | LPR!NT | ESCl:CHR((421ICHRI(O): |
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30 REtIDefinecwyrightsvmbolin place | of Q | |||
40 | LPR!NT ESC~ICHRS(~~):CHR((I):CHR$(~~):CHR~(O)~CHR$~~S)~CHR~~~~)ICHR$~?~!~ | |||
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| ~HRi!iO~~CHR1~6S~~CHR(oleHRllbS!ICHR$~S4~~CHR~f~O~~ | ||
44 REN Deflnrcotwrightsvmbol | in olrce | of t | ||
45 | LPRINT | ESC(ICHR((~~)~CHRI(~I~~HRI(~~)~CHR~~~)~CHR~(~S~~CHR~(S~!~CHR~(~~): | ||
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| CHR~!~~):CHR~(~S)ICHR~(~O)ICHR~~~~)~CHR~~~~)ICHR~~~O~~ | ||
$0 REF Select downloadrble chtrrcters |
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60 | LPRINT | ESClleHRI(56)lCHRI!l) | I |
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70 | REM | Printournw rvmbols |
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90 | LPRINT | “W&@!&@tlt@tb&” |
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Figure |
| to print: | y :::.?:....,;;x.‘?..q../r?:”.Q .?r^.” p | |
,,i I..,. .>n:,. | ||||
One more instruction you’ll need before we leave downloadable characters: How to turn them off.
CHR$(27) CHR$(36) CHR$(O)
Turning downloadable characters on or off during a line will affect a// characters on that line. In other words, if you turn on downloadable characters anywhere in a line, all of the characters on that line will be treated as downloadable characters.
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