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-the “control” key and one other. The other key determines what code is sent - pressing the control (CTRL) key and A sends ASCII code 1, CTRL B sends ASCII code 2, and so on. Your printer has a lot of control codes to let you do some useful things. Let’s try one that we’ve mentioned several times
already:
'Demo of ASCII code :i LPRINT CJlR$(7)
30 END RUN
That’s the printer’s bell (we call it that even though it sounds like a buzzer). We’ll learn more about it in later - we just wanted to show you a control code that would get your attention right away!
There are four common ways of referring to a control code: the name of the code or its abbreviation, the decimal ASCII value, the hexadecimal ASCII value, and the
line feed | - | the | name | of the | code |
| |
(LF> |
| - | its | abbreviation |
|
| |
ASCII | 10 | - | its | decimal value |
|
| |
ASCII | &HOA | - | its hexadecimal | value (the | &H | ||
|
|
| signifies | hex) |
|
| |
CHR$( 10) | - | the | way | it’s used | in BASIC | ||
CTRL- J | - | the | way | you send it from | a keyboard |
Of course, most of the time we don’t need to bother with these. The computer is smart enough to know that when we press the “A” key we want to print the letter “A” - it takes care of all the intermediate steps.
Appendix B is a table that shows the various names for each code so you can convert back and forth. The microcomputer world is not very consistent in describing ASCII codes, so it’s important that you have a basic knowledge of them.