Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!snorkelwacker.mit.edu!stanford.edu!unix!hplabs!hp-pcd!hpcvra.cv.hp.com!rnews!hpcvbbs!akcs.jwtrav
From: akcs.jwtrav@hpcvbbs.UUCP (John Wettroth)
Newsgroups: comp.sys.handhelds
Subject: Re: 48SX: Hardware project to receive I/R I/O
Message-ID: <27f4511b:2500.1comp.sys.handhelds;1@hpcvbbs.UUCP>
Date: 30 Mar 91 09:40:07 GMT
References: <1371@cameron.egr.duke.edu>
Lines: 8

The HP-48 ir couldn't be simpler.  Look at it on a scope.  It is just a
uart driving an led.  Receiving the ir over short distances can be done
easily with a photo-transistor.  The book referenced in 48 manual about
Kermit (by Cruz) has more in it about Kermit than any human could ever
want to know.  Its about $30 at any good college bookstore.  Kermit needs
a microcomputer to implement, a state machine doesn't make much sense. 
As far as my luck with HP-48 ir, I sell a small data acquisition and
control system (available from Edu-Calc) that is controlled over the IR
link. Good luck.