From: jwmills@iuvax.cs.indiana.edu (Jonathan Mills)
Newsgroups: comp.sys.palmtops
Subject: Re: derive for HP95LXS
Date: 23 Dec 91 16:36:18 GMT
Organization: Computer Science, Indiana University, Bloomington.

In article <1991Dec23.110836.29167@uc.msc.edu> eab@uh.msc.edu (Edward Bertsch) reports:
>
>From NASA tech briefs, December 1991, page 69
>
>
>DERIVE: a compact card for the HP 95lx
>(this software also runs on 8088->80486 machines)

David Stoutemeyer, primary author of Derive, told me in a telephone
conversation that Derive for the HP95LX has been optimized to sleep
between keypresses etc. to conserve power.  He said that the HP95
version should *not* be expected to run on any other PC.  HP95 Derive
*does* run under SoftPC on a Macintosh, but implements only the (ugly)
25x80 column text interface.  That surprised Mr. Stoutemeyer, who
suggests that SoftPC must not implement the interrupts that would
otherwise prevent HP95 Derive from running on a PC.

SoftWarehouse omitted the other display drivers from HP95 Derive,
apparently to free up memory.  But the ROM card has room for the drivers,
and only one is used at a time.  It would have seemed much better
to have made the drivers selectable independent files.  But, as
Mr. Stoutemeyer also suggested, SoftWarehouse's solution is for you
to buy the PC version of Derive if you want to run the program on a PC, too.


>System requirements:
>PC version:
> ms dos 2.1 or later, 512kb ram and one 3.5" or 5.25" disk drive
>suggested retail $250
>
>ROM-card version
>HP 95lx palmtop, suggested retail $289

Also from Mr. Stoutemeyer:  Try CompuClassics, 7959 Deering Ave.,
Canoga Park, CA, 91304, 1-800-733-3888.  They carry PC Derive
and HP95LX Derive on diskette, both deeply discounted:

	PC Derive	$135
	HP95LX Derive	$169

If the Derive .HLP file is left off, you can fit HP95LX Derive on a
256K RAM card (Sparcom makes a 256K RAM, priced somewhere around $150).
You can use the RAM card for other things than Derive, too.

>I have used derive. it is really good software, and doesn't need a killer
>machine to do killer work..
>
>--
>Edward A. Bertsch (eab@msc.edu)        Minnesota Supercomputer Center
>Operations/User Services               1200 Washington Ave. S.E.
>(612) 626-1571                         Minneapolis, Minnesota  55415

As usual, back up your HP95 files before running Derive.  To activate
Derive on the HP95 you must do a CTRL-ALT-DEL.  Derive then uses a
program called RAMCRAM to free all unused 95 system memory allocated
to the 95's C: drive.  It is not supposed to trash C:, but I had one
so-far-unreproducible error where the HP hung in an "on" state, and
refused to respond to the keyboard or anything else.  I removed all
the batteries and re-initialized the 95, then restored from a backup
to save all but the Derive files I'd created during that session.

Other than that, Derive is pretty nifty:  fitting somewhere between
Theorist and Mathematica, but capable of being carried around in your
pocket.  It would be nice if Derive had an RPL-like language, but it
does not.  Version 2.0 does have assignments, iteration, recursion,
and nested IF statements, plus a heap of functions, though.  It takes
some getting used to, less if you have programmed the HP27 or in
Prolog (that's what it "feels" like, IMHO).

From uwm.edu!cs.utexas.edu!uunet!decwrl!pa.dec.com!nntpd2.cxo.dec.com!nntpd.lkg.dec.com!math.zko.dec.com!edp Wed May  6 01:05:51 CDT 1992
Article: 2097 of comp.sys.palmtops
Newsgroups: comp.sys.palmtops