Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!elroy.jpl.nasa.gov!sdd.hp.com!hp-pcd!hpcvra.cv.hp.com!everett
From: everett@hpcvra.cv.hp.com. (Everett Kaser)
Newsgroups: comp.sys.handhelds
Subject: Re: HP95LX  -  some thoughts
Message-ID: <25590165@hpcvra.cv.hp.com.>
Date: 17 May 91 15:03:37 GMT
References: <9105162236.AA08605@ucbvax.Berkeley.EDU>
Organization: Hewlett-Packard Co., Corvallis, OR, USA
Lines: 61


 SPGJAF@CMSA.BERKELEY.EDU (Joseph A. Faracchio) writes...
>But ... I'm confused.  It takes only 1 Ram/Rom card and you can only get 512K
>max on it.  And you can't do 640K Dos and 384K for data/prog.  The card is used
>'like a floppy' meaning data is saved?  (Like the Wizard where you can walk
>around with any number of 32/64/128K cards 'like floppy disks'.)
>If keept at 512K/512K makeup can the card be pulled out without losing data?
>If it can work with a 2 meg card why isn't one offered?

The HP 95LX has 512K of RAM built-in.  This 512K is split (in proportions
specified by the user) into USER RAM and dirve C: RAMDISK.  The default that
the machine comes up at is about a 50-50 split.  The plug-in card is treated
as drive A:, just like a floppy on a desktop PC.  The cards can be pulled and
another inserted at any time.  The HP 95LX was designed to accept cards up to
2M bytes in size, because ROM cards are already available in that size, and
RAM cards will be available in that size easily within the product life-time
of the HP 95LX.

>Is there no password capability?  I'd like to lock out people from some/all

Yes, there is password security.  This is documented in the manual.  Once
you've set a password, you can set AUTO-LOCK or MANUAL-LOCK mode.  In AUTO
mode, any time the machine turns off, the password will be required before
access is allowed.  In MANUAL mode, the machine is only secured when you turn
it off by holding down the ALT key and then pressing and releasing the ON key.

>The screen management.  Ideally I envision a situation where there is an 80x25
>display buffer always present and if my application doesn't know any better it
>can write to this 80x25 buffer and I can use special meta-keys (unknown to the
>application) to page left-right/up-down to see the whole screen.  Is that
>the way it works?

Yes, that is the way it works.  All of the built-in applications have been
adapted/designed to work on the 40x16 display, but when you go to the DOS
prompt (and/or run other programs from the Filer), the display pans around on
an 80x25 display.

>Can any non-graphical software work right out of the box?  I'm asking in fact:
>is it true XT-compatible or more like the PortFolio : an MS-Dos lookable.
>I want to run my own comm prog and Mansfield Software's Personal Rexx  (300K).
>If I overcome the space limitations (512/512) will they work??

Yes, it is "true" XT-compatible, within certain obvious limits.  The BIOS is
from Phoenix (with some HP modifications to fit the hardware), DOS is 3.22
from Microsoft (ROM executable, the DOS code doesn't load into RAM), and all
of the PC "glue" circuitry (except the CPU, RAM, and ROM) is in a single ASIC
chip manufactured by Intel, which includes the interrupt controller, timer,
UART, CRT (LCD) controller, keyboard control, etc.  The only programs we've had
any problems with are ones that make assumptions about the hardware (or talk
directly to hardware) that just isn't true for the HP 95LX.  Examples are
programs that talk directly to floppy and hard disk controller cards or
parallel ports, CMOS setup RAM, require a DMA controller or require a
CGA/EGA/VGA/Hercules display (the HP 95LX has an MDA compatible display, which
had one page of text and NO graphics;  the HP 95LX graphics are a non-standard
proprietary design).  So, as long as a program is text only, and talks to the
display ONLY through DOS, the BIOS, or knows how to detect an MDA display and
talk directly to its video RAM, then the program should work.

Everett Kaser                   Hewlett-Packard Company
...hplabs!hp-pcd!everett        work: (503) 750-3569   Corvallis, Oregon
everett%hpcvra@hplabs.hp.com    home: (503) 928-5259   Albany, Oregon