In January 1972, Hewlett-Packard introduced with the HP-35 the first scientific
pocket calculator with transcendental functions and revolutionized the way to
calculate. 2011 Pietro de Luca created (based on the work of Peter Monta and
Jacques Laporte) a port of the reverse engineered HP-35 ROM for AVR
microcontroller.

HP3542 uses this HP35-ROM-Engine to offer the calculation power of the HP-35 to
the DM42 calculator of Swissmicros (with finally less then 9 Kilobytes).

Have fun!
deetee


____________________

 INSTALLATION
____________________

Please note that you will loose all user data of your DM42 (ie. user programs or
settings) - make a backup!

Install HP3542:

 * First load HP3542-xxx.pgm and (for desired later back switch to DM42)
   DM42-x.xx.pgm (technical.swissmicros.com/dm42/firmware/) to the root directory
   of the USB disk.
 * In your DM42 calculator goto SETUP (SHIFT-0)
 * Enter menu point [5. System >]
 * Goto system menu with [2. Enter System Menu]
 * Leave DM42 and switch back to the operating system (DMCP) with
   [3. Reset to DMCP menu]
 * Load another program with [3. Load Program]
 * Select the HP3542 program [HP3542-xxx.pgm]
 * [Confirm with ENTER]
 * [Press any key to start]
 * [Press EXIT to continue ...]
 * You are running HP3542 - have fun!

Reinstall DM42:

 * Switch back to the operating system (DMCP) with SHIFT
 * Load another program with [3. Load Program]
 * Select the DM42 program [DM42-x.xx.pgm]
 * [Confirm with ENTER]
 * [Press any key to start]
 * [Press EXIT to continue ...]
 * You are running DM42 - thanks for trying HP3542

____________________

 SPECIAL KEYS
____________________

SHIFT  Exit HP3542 to the operating system (DMCP)
EXIT   Enter suspend mode of DM42 (OFF)
F1     Not assigned key - shows the battery level (0...9; <=2.5V ... >=3V)


____________________

 HP-35 LAYOUT
____________________

     _________________________
    |                         |
    |     -1.234567890-12     |
    |_________________________|
    |                         |
    | X^Y  log  ln   e^X  CLR |
    | SQRT arc  sin  cos  tan |
    | 1/X  X><Y ROT  STO  RCL |
    | E-N-T-E-R CHS  EEX  CLX |
    |   -     7     8     9   |
    |   +     4     5     6   |
    |   *     1     2     3   |
    |   /     0     .     PI  |
    |_________________________|