From: gtoal@an-teallach.com (Graham Toal)
Date: Fri, 20 Aug 93 11:51:35 PDT
To: cypherpunks@toad.com
Subject: building a sound sampler for cryptophone application...
Message-ID: <6263@an-teallach.com>
MIME-Version: 1.0
Content-Type: text/plain


In article <9308201757.AA04239@soda.berkeley.edu> hughes@soda.berkeley.edu writes:
 > That said, I think that designing custom hardware for sound sampling
 > is a waste of time, given the abundance of multimedia cards that
 > already work.
 
Yes, but have you ever tried to drive them from a C program?  From the
scanty docs I got with my Soundblaster, I wouldn't know where to start.
And I get the impression that there's a major cpu overhead with these
cards, like you can't actually do anything useful apart from grab the
data.  I want the data input to be free so there's CPU left over for
compression and encryption and network or modem driving, without having
to use a 66MHz 486 to do it...
 
Oh, and multimedia cards are pretty expensive.  This will cost maybe $25
at most.  It's the sort of thing that once designed, hardware-inclined
cypherpunks could hack up dozens of at home and pass them on at 
conventions like HoHoCon or the one we just had in the Netherlands...

 > While I applaud your enthusiasm, your effort toward getting usable
 > secure phones would be much betting spent writing device drivers for
 > various soundblaster-type cards.

*My* effort already is being better expended elsewhere.  As I said, my
old uncle has time on his hands and wanted suggestions; I thought it was
better not to squander such an opportune resource on junk like chiming
doorbells when he could be doing something for us just as easily.

Now, if anyone actually has an answer to the question, which was about
how to drive a PC parallel port for input, do let me know please.

regards

Graham
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