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.

DM11, DM12, DM15, DM16:
KeysFunctionDescription
[ON]+[B]benchmarkevaluate benchmark compared with orig. calc              
[ON]+[C]serial consoleswitch to serial console (see below)
[ON]+[E]show informationfirmware version & battery voltage
[ON]+[CHS]LCD settingschange LCD contrast with buttons [+],[-],[3],[Σ+]
[ON]+[7]change fontcycle through three fonts
[ON]+[9]change speedtoggle between 12MHz and 48MHz
[ON]+[/]key testsame as on the original calculator
[ON]+[×]self testsame as on the original calculator
[ON]+[-]power resetsame as on the original calculator
[ON]+[+]endless testsame as on the original calculator
[ON]+[.]toggle . and ,same as on the original calculator
    

DM41:
KeysFunctionDescription
[ON]+[C]serial consoleswitch to serial console (see below)
[ON]+[E]show informationfirmware version & battery voltage
[ON]+[CHS]LCD settingschange LCD contrast with buttons [R/S],[3],[2],[.]
[ON]+[8]change speedtoggle between 12MHz and 48MHz
[ON]+[9]key testkey test similar to the one known on the other models
[ON]+[STO]-1hset the clock -1h: daylight saving and changing timezones
[ON]+[RCL]+1hset the clock +1h: daylight saving and changing timezones
    
Follow these steps to enter the console:
Turn off the calculator, press and hold [C], press and release [ON], release [C]
Serial Console
Battery replacement
Change LCD contrast
Change font The models DM11, DM12, DM15 and DM16 include three font types: slim, bold and block
The combination [ON]+[7] cycles through all three font types