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From: Jake-S@cup.portal.com (Jake G Schwartz)
Newsgroups: comp.sys.handhelds
Subject: HP48 Internals, etc
Message-ID: <38752@cup.portal.com>
Date: 2 Feb 91 01:28:39 GMT
Organization: The Portal System (TM)
Lines: 24

This is for Joe Horn, Derek Nickel and any others out there who are dabbling
in the "underworld" of HP48 internals.

The version of Derek's Voyager that I have (1.0-1 from Las Vegas) contains
a dump of the HP48 version B ROMS. In order for the serious developer to 
be certain that his code runs on all versions A to E of the machine, it 
might be wise to provide dumps of ALL FIVE versions fo the HP48 ROMS. I'm
sure that nobody owns all 5 versions his or herself, but perhaps it would
be prudent if ultimately we collected all these dumps and provided them 
with the Voyager package???

(This begs the converse of the most ofter-asked question on this group:
"How do I know that the code I have will run on the version of the ROMs tha
I own?")

At some point, it might be wise to find out which routines that exist in our
collective HP48 address list are in different places for different ROM 
versions. I know Rick Grevelle has a routine that searches ROM for all 
entry points to RPL prefixed code. At the very least, if this routine was
run on all 5 versions, we could compare the output address lists to see if
any of these entry points have moved. Perhaps these are in the list of
rumored "Protected Addresses" which HP plans to leave alone.

Jake Schwartz