(Comp.sys.handhelds)
Item: 2695 by darrylo at hpnmdla.hp.com
Author: [Darryl Okahata]
  Subj: How to backup the ENTIRE HP-48SX memory
  Date: Mon Apr 08 1991

     Here is a beta-release of a program to backup the ENTIRE contents (libs
and all) of an HP-48SX.  It's not perfect, it's huge (about 1000 bytes), and
it's probably inefficient (I just slapped this together).

     Also, while I've tried to work out any bugs, there's no guarantee that it
works.  ;-)

     The big advantage of these functions, over previously-released ones, is
that you only need as much memory as the largest library/port variable to do a
backup, as the libraries/port variables are saved in separate files and not as
a concatenated list in main memory.

     The code at the end of this message contains two functions: BACKUP and
RECOVER.  In order to use these functions, you need to backup to a kermit
SERVER; you must place the destination machine in kermit SERVER mode to use
these routines.  If you do not have a kermit that supports SERVER mode, you
cannot use these routines.  You must also use binary transfer mode; if you
accidentally use ASCII mode, the transfer will take hours.  Also, the clock
display must be turned off, due to the archive bug; if the display is turned
on, the clock will be turned off, and you will be asked to redo the operation.

     You press BACKUP to archive the contents of your HP-48SX.  BACKUP sends
each variable/library to the kermit server, one by one (it first checks to see
if you have enough memory, though).  They are stored in files named like:

     Lpnnn

     Where "p" is the port number (0..2), and "nnn" is a number from 1 to
however many variables are in the port.  As each port object is sent to the
server, a note of its type (variable vs library) is made and is saved away
(this is used to restore the backup).  After all port objects have been saved,
the flags are saved in a variable, and an ARCHIVE is done (the ARCHIVE file
name is hard-coded to "BACKUP").  The HP-48SX will also terminate the kermit
server at the end of the backup.

     Filename collisions are a problem here.  I strongly suggest starting the
kermit server in an empty directory before starting the backup.

     Here's a summary of the backup process:

1.  Make sure the HP-48SX is using wire/binary transfer.

2.  Place kermit into SERVER mode.

3.  Press BACKUP.  Have a cup of coffee while you wait.  If the suppress error
    beep flag (-56) is not set, the calculator will beep when the full backup
    is complete.

     To restore the contents of your HP-48SX, you do the following:

1.  Go to the directory containing the backup files.

2.  Using kermit, transfer the "backup" archive back to the HP-48SX, and
    RESTORE it.

3.  Put kermit into server mode.

4.  Go to the HP-48SX directory that contains the BACKUP and RECOVER functions.

5.  Press RECOVER.  The calculator will transfer the necessary files and place
    the objects into the correct ports.  That's it.


***** Known problems:

* This program backs up EVERYTHING in RAM (of course, it doesn't touch ROM).
  It backs up *ALL* libraries, backup objects, other variables, etc..  You
  cannot tell it to not backup something, other than purging the object, or
  pulling the RAM card out of the calculator.

* This program is huge, due partly to the extensive checks that makes sure that
  enough memory is present before doing the BACKUP/RECOVER.  Perhaps these
  checks should be deleted (but I like having user-friendly programs ...)?

* No kermit error checking is done.

* Currently, some of the constants used to estimate the minimum amount of RAM
  needed are stored in variables ("M" and "S").  Perhaps these should be
  hard-coded?

* The current set of functions can be placed anywhere, as long as the directory
  hierarchy is maintained.  Some RAM can be saved if these functions were
  hard-coded to work in a particular directory (such as "{HOME BACKUP}").  Does
  anyone have any preferences?

* Does anyone know how to force binary kermit transfers?

* I consider this to be a beta-release.  As such, the code is not commented.

     -- Darryl Okahata
        UUCP: {hplabs!, hpcea!, hpfcla!} hpnmd!darrylo
        Internet: darrylo%hpnmd@relay.hp.com

DISCLAIMER: this message is the author's personal opinion and does not
constitute the support, opinion or policy of Hewlett-Packard or of the little
green men that have been following him all day.

----------
  Resp: 1 of 1 by cook at hplvec.LVLD.HP.COM
Author: [Steve Cook]
  Date: Sun Apr 28 1991 22:53
 Lines: 3

I found that the hp48 has to be in STD mode before the backup routine will work
properly.  This is a handy program.  Thanks for your effort, Darryl.

[STD is in the program on disk.  -jkh-]