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Re: help diagnosing an Apple IIe, please.



In article 
<52bcece6-7077-4ded-8858-2f1218d727b6@q30g2000prq.googlegroups.com>,
 adric22 <adric22@yahoo.com> wrote:

[...]
> Well I'm an old school C64 programmer, so let me ask you this.  How do
> you write a program in BASIC that continues to loop and do stuff while
> waiting for a keypress?  For example, I was trying to write a simple
> drawing program for the low-res graphics mode and I wanted it to blink
> the pixel it was currently sitting on when no keys were being
> pressed.  How would I achieve this?  On the C64 we would use a command
> like this:
> 
> 10 GET A$: IF A$ = "" THEN GOTO 10
> 
> That would achieve the same thing as the GET statement alone achieves
> on the Apple, but I could remove that GOTO 10, and put it at the end
> of several other commands.. That way those commands would continue to
> execute until something was pressed.

Maybe something like this?

10  HOME :A$ = " ": ONERR  GOTO 90
20  PRINT "Press any key; ^C exits."
30  KB = -16384 : KC = KB +16
40  IF PEEK(KB) >  128 THEN POKE KC,0 : A$ = CHR$(PEEK(KB))
50  VTAB 12: PRINT ">  ";A$
60  VTAB 12: PRINT "-> ";A$
70  VTAB 12: PRINT "-->";A$
80  GOTO 30
90  END

-- 
John B. Matthews
trashgod at gmail dot com
<http://sites.google.com/site/drjohnbmatthews>