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From: mh2f+@andrew.cmu.edu (Mark Hahn)
Newsgroups: sci.electronics
Subject: microcomputer with a-d and d-a?
Message-ID: <IbfnAi600VpbA3pEw1@andrew.cmu.edu>
Date: 5 Feb 91 22:35:26 GMT
Organization: Carnegie Mellon, Pittsburgh, PA
Lines: 15

I've been thinking about building a little device
to record and play back digitized sound.  the idea
would be to have d-a and a-d converters hooked up to
a single-chip micro with, say, a megabyte of low-power
static ram.  even something as wimpy as a 68HC11
could do linear predictive coding, compression or even
(non-realtime) speech analysis.  the device could
also be a dictating machine, appointment book, etc.

know of any microcontrollers with converters on-chip?
recommendations on d-a and a-d converters?
how does speech sound using a zero-crossing detector?

thanks,
mark