Newsgroups: comp.sys.handhelds
Path: utzoo!utgpu!watserv1!mann
From: mann@watserv1.uwaterloo.ca (Shannon Mann)
Subject: another hp48 question
Message-ID: <1991Jun15.042317.25978@watserv1.waterloo.edu>
Sender: mann@watserv1.waterloo.edu (Shannon Mann)
Organization: Computing Services, University of Waterloo
Date: Sat, 15 Jun 1991 04:23:17 GMT
Lines: 28

Hi. I am the same person who recently asked those hp48 questions since
I'm thinking of upgrading from my 28. Incidentally, I am not that person
(Shannon). I am his friend Terry. i.e. that posting and this one - we're
both Terry. (got it?) (SM knows I'm here!)
	Thank-you, all, for the feedback (but don't stop). I just read
the summary posted by someone (sorry) regarding the fact that the 48 misses
keys. I hope this is not a great problem since I sometimes do a lot of
number crunching (coursework) and just sold my 28... I'm committed... Maybe
I should just go buy a Sharp or Casio instead (JOKE! Haha! ha! err... hmm.)
	One "last" question... I heard that several companies that make
laptop PCs agreed on a standard for plug-in memory cards. Dare I suppose
this is that used by the 48SX? My idea here is that if the cards were an
industry standard, they would get cheap quick. Perhaps, at least, they may
be equivalent electronically only ie. different case and connector? I would
expect that the only critical characteristics would be control signal
protocol (CS, R/W or RE, WE or whatever) and addressing scheme (number of
bits address, bits data). Hopefully timing (setup, hold, access times) would
take care of itself. Access times should be OK since 48SX hardware is older
(?). And even if the 48SX has fewer data bits, it could merely access a
subset of the generic card. If the control signals were different, perhaps
a gate or 2 would work. I assume they both use lithium-cell backed CMOS
static RAM. Do the docs exist to check this out? Being forced to
use a different connector may be a reason to save some bucks and hack it
onto a plain 48S. Which brings me to my last+1 question: what precisely is
the difference between the 48SX and 48S? Just an empty card bay with no
connector? Or no case door either? Important: do the memory card config-
uration routines still exist in the 48S?