SwissMicros | Instructions

Key Combinations The DM calculators have some special key combinations, some are the same as on the HP calculators, some are unique to DM calculators.

Buttons Function Description
Press & Hold     Press & Release
[A] + [ON] display time/date display time/date for 5 minutes
[B] + [ON] benchmark evaluate benchmark compared with orig. calc
[C] + [ON] serial console switch to serial console (see below)
[E] + [ON] show information firmware version & battery voltage
[CHS] + [ON] LCD settings change LCD contrast with buttons [+],[-],[3],[Σ+]
[STO] + [ON] daylight saving adjust RTC decrement -1h
[RCL] + [ON] daylight saving adjust RTC increment +1h
[7] + [ON] change font cycle through three fonts
[9] + [ON] change speed toggle between 12MHz and 48MHz
[/] + [ON] key test same as on the original calculator
[×] + [ON] self test same as on the original calculator
[-] + [ON] power reset same as on the original calculator
[+] + [ON] endless test same as on the original calculator
[.] + [ON] toggle . and , same as on the original calculator
new in V23:
[SST] + [ON] start time/date adjustment use [/], [x], [-], [+] to change and [ENTER] to set

Serial Console
  • set calculator in serial console mode by [C]+[ON]
  • connect miniUSB cable to computer. drivers for many platforms including Win, MacOSX, Linux can be found here
  • open terminal program; on windows putty (or hyperterm if you are brave enough), minicom under linux, use Terminal under MacOSX
  • for Linux/MacOSX find the device using "ls /dev/ttyUSB*" or "ls /dev/tty.S*" if you installed silab driver
  • set terminal program to 38400,8n1 (no flow control) (for example on Linux use "minicom /dev/tty.SLAB_USBtoUART 38400,8n1" or on MacOSX "screen /dev/tty.SLAB_USBtoUART 38400,8n1")
  • en- and decode utility (html with jscript) for RAM save and restore function
  • a great HP-15C Simulator for Windows, Linux and Mac OS Xsupports data exchange with the DM15
  • instructions for the serial console for Mac and Windows (PDF)
Battery replacement
  • turn calculator off; the content remains for about 30 seconds without battery
  • unscrew all four screws
  • remove calculator from case
  • replace battery
  • put it back together, don't tighten the screws too much
Change LCD contrast
  • [CHS]+[ON] starts the LCD mode setting
  • use [+], [-], [SUM+] and [3] to change the contrast
Change font The models DM11, DM12, DM15 and DM16 include three font types: slim, bold and block
The combination [7]+[ON] cycles through all three font types