Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!ux1.cso.uiuc.edu!uxa.cso.uiuc.edu!jb10320
From: jb10320@uxa.cso.uiuc.edu (Jawaid Bazyar)
Newsgroups: comp.sys.apple
Subject: Re: cassette click
Message-ID: <1989Oct24.000408.8164@ux1.cso.uiuc.edu>
Date: 24 Oct 89 00:04:08 GMT
References: <2390@eagle.wesleyan.edu>
Sender: paul@ux1.cso.uiuc.edu (Paul Pomes)
Reply-To: jb10320@uxa.cso.uiuc.edu (Jawaid Bazyar)
Organization: University of Illinois at Urbana-Champaign
Lines: 43

In article <2390@eagle.wesleyan.edu> dkonerding@eagle.wesleyan.edu writes:
>
>	Hello, folks.  I sense the UPS man approaching with my IBM clone; it's
>a matter of days.  I'm trying to cram all the work I always wanted to do into
>about 72 hours.  One thing I'm doing to trying to get a check the cassette in
>byte and see if there's sound coming in,and if so, click the speaker-- in
>effect, making the Apple speaker sound like whatever my tape is playing.  I
>know that people have taped their voices and played them back with the Apple,
>the following program won't do the first job I mentioned:
>LDA C060 (or whatever the cassette-in byte is)
>CMP #A0 (160 seems to equal "no sound")
>BNE TOP
>BIT C030... all this does is click the speaker when sound is coming in, no
>pitch, nothing.  How can I get this to work?
>
>	Thanks.
>
>-- 
>	Remember, while having sex, always, always wear a condiment.
>DKONERDING@EAGLE.WESLEYAN.EDU
>DKONERDING%EAGLE@WESLEYAN.BITNET

   As far as I remember, only one bit in the C060 (or whatever) cassette-in
port is actually functional. I assume this is the high bit (7 or 8 for those
of you who prefer).  What you really need to check for is something like this:
LDA C060
BPL TOP
BIT C030
BRA TOP

   In addition, you might need to put some sort of delay in this loop,
as this loop executes at around 100,000 times per second, far faster than
the resolution of the speaker and sound hardware on the //e.
   Alas, I have only a GS with no cassette port to test my ideas.

--
===============================================================================
jawaid bazyar    jb10320@uxa.cso.uiuc.edu  Junior/Computer Engineering UIUC

Seepage from deep,black,brittle experiments which failed and transformations too
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