Commodore Plus 4 - Page 182

Reprogramming Function Keys
You can reprogram the function keys to match the function keys on the
Commodore 64 and VIC-20. (This also makes program conversions H
from those machines easier).
To reprogram the keys, put the following line into your program:
10FORI=1 T08:KEYI, CHR$(I+132): NEXT
Now whenever you type a function key, it sends a non-printing
character, from 133 to 140, like the Commodore 64 does. To check for —
this in a program, you can use this method;
20 GETKEY A$: IF ASC(A$) -133 THEN PRINT "FUNCTION KEY 1
HIT": GOTO 20
30 IF ASC(A$) > 133 AND ASC(A$) < 141 THEN PRINT "SOME
OTHER FUNCTION KEY HIT"
40 GOTO 20 —
After your program is done, you have to redefine the keys again if you
want them to say directory, dload, etc. You can do this by hand, in a
program, or by resetting the Plus/4.
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