Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!mcsun!ukc!icdoc!cc.ic.ac.uk!umapd51
From: umapd51@cc.ic.ac.uk (W.A.C. Mier-Jedrzejowicz)
Newsgroups: comp.sys.handhelds
Subject: Re: More on ROM extraction
Summary: You can move an HP48 card 100,000 times, and a machine code card
Keywords: HP48, memory cards, HP48 machine code programming
Message-ID: <1991Feb5.043431.3182@cc.ic.ac.uk>
Date: 5 Feb 91 04:34:31 GMT
References: <10594@jarthur.Claremont.EDU> <TT.91Feb1155646@sonja.jyu.fi>
Sender: Wlodek A.C. Mier-Jedrzejowicz
Organization: Imperial College Computer Centre
Lines: 26
Nntp-Posting-Host: suni2cc


Among Tapani Tarvainen's remarks on the problem of moving HP48 cards is
a question - can he swap a plug-in card 5 times a day for 10 years?
Tapani (and all others interested) - the specs say the cards are good
for 100,000 insertions. Five a day for 10 years comes to less than
20,000 - so you should have no problems! 20,000 swaps at about 6 seconds
a swap (see earlier messages) would accumulate to 33 hours of
card-swapping though, not to mention the grief every time you forgot to
save the stack. For these reasons alone - ignoring all discussion of
program copying - more slots would have been very welcome -
unfortunately they would have led to a bigger calculator.
Maybe page-swapping cards WILL be available though. I am in
communication with the German company W&W (makers of the HP-41 CCD
module) who claim to be producing 512K, 1Meg and 2Meg cards for the 48.
I am still waiting for details of these, but if they ever do come into
existence they will have to use page-swapping since the HP48 has a
memory space of only 512K bytes.
By the way, W&W claim to have a machine code programming card already on
sale, and have invited me to translate the manual into English, but I
have not yet received the card and manual. When I do get them I hope to
report here - and at the same time to answer Bill Gribble's question
whether I could write a machine language programming book for the HP48
in the wake of my book on the HP28.
Wlodek Mier-Jedrzejowicz, Ph.D., Space & Atmospheric Physics, Imperial
College, London.
BITNET address (I prefer to use it) MIER@ SPVA.PH.IC.AC.UK