SwissMicros DM-15CC

Serial number None
Accessories Pouch
Condition Bought new
Repairs, Comments On 28.3.2012 I updated my two units to V3 firmware. This was a major desaster until I finally found out that the FlashMagic programming software V6.30 was buggy. Luckly, an older V6.03 copy worked just fine. Later that day version 6.31 became available!
28.4.2015 updated both units to the V16 firmware version.
Acquired 28.3.2012, two units

Type, Precision, Input mode Scientific, 10 BCD digits, exponent 99, Reverse Polish Notation
Programmable Yes
Performance Index 9.2 (original HP-15C: 2.7, HP-15CLE from 2011: 195, iPhone4 implementation: 485)
The 15CC is about 3.4 times faster than the original HP-15C but 21 times slower than HP'2 new Limited Edition version.
CPU & Memory LPC1114 ARM CPU emulates the NUT processor. Permanent memory.
Display 132x16 pixel dot matix LCD display
Special features Mini-USB connector for external access,  eg program saving, operating software update.
Reportedly, it does not exhibit the HP-15C Limited Edition Bugs.
Original Pricing, Production Designed and produced by Michael Steinmann since 2011, 48 Euro in early 2012.
Now (2015) produced and sold by SwissMicros.
Batteries One button size cell. To replace the batteries unscrew the back of the unit and remove the small cover bar in front of the battery. Do not tighten the screws too much when reassembling the unit!
Dimensions Length 5.7cm, Width 8.1cm, Height 0.8cm
Links rpn-calc by Michael Steinmann., see there for firmware updates.
For manuals see HP-15C. See also DM-41 and DM15L.
Forensic Result9.000417403 - identical to the classic HP-15C. This is to be expected since the processor emulates the original CPU and presumably uses large parts of the original ROM code.
Comment See the HP-15C for a list of exciting news on the 15C.
What a cool device! The unit is small and rugged, the dot-matrix display looks very good.
Of course the keys cannot rival the original HP buttons.
Key Combinations Turn off calculator, press and hold the function key, press ON briefly, release the function key.
Function key Action
B Benchmark, returns a value close to 9 indicating that the unit is almost 9 times faster than the original HP-15C. My own benchmark doesn't quite match this number.
This test does not seem to be available in V3 any more.
C Turn on serial console
7 Toggle between 7-segment font and smooth font
/ Key test, same as on original 15C - doesn't quite work!
* Self test, same as on original 15C 
- Reset, same as on original 15C
+ Self test, same as on original 15C
, Switch between comma and dot for fraction delimiter
E Shows the firmware version (as long es "E" key is depressed). Only available starting from version V3

Software Update There is a number of different firmware versions available on the rpn-calc / SwissMicros site.
For programming details see DM-41. The difference is that my DM-15CC units only have one tiny pinhole in the back which requires a needle to be used. This pinhole servers as PGM button to start programming and RESET button as well. To turn on the serial console use ON+C.
The 15CC hardware only supports 32kB of flash memory so the "DM15CC" or "32k" firmware versions must be used.
Note: If the unit seems dead after programming briefly remove the battery (unscrew back lid).
Program used to determine the performance index for the DM-15CC, HP-15C LE and HP-15C Classic:
001 LBL A
002 10
004 STO 0
005 LBL 1
006 1
007 +
008 4.567E-4
016 -
017 70
019 +
020 69
022 -
023 7
024 x
025 11
027 /
028 RCL 0
029 1
030 -
031 STO 0
032 x<>0? (TEST 0)
033 GTO 1
034 Rv
035 log
036 sin
037 sqrt
038 sqrt
039 RTN
Wrapper with count in reg 3:

040 LBL B
041 GSB A
042 RCL 3
043 1
044 -
045 STO 3
046 x<>0? (TEST 0)
047 GTO B
048 RTN
With 5 loops specified in register 3 the program runs for 18.6 seconds.
The performance index calculates to 34 * 5 / 18.5 = 9,2

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