SwissMicros DM-15L

Serial number On the back of the unit "S/N # 00358"
Accessories Pouch
Condition Bought new
Repairs, Comments
Acquired 24.9.2015

Type, Precision, Input mode Scientific, 10 BCD digits, exponent 99, Reverse Polish Notation
Programmable Yes
Performance Index 34 - the original HP-15C reached 2.7
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 operating software update.
Original Pricing, Production Produced and sold by SwissMicros. (Michael Steinmann), 126 Euro in 2015, includes shipping from Switzerland
Batteries One button size cell. To replace the batteries unscrew the back of the unit.
Dimensions Length 12.9cm, Width 7.9cm, Height 1.4cm
Links rpn-calc by Michael Steinmann., see there for firmware updates.
For manuals see HP-15C. See also DM-41 and DM-15CC.
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 has the same size as the original HP-15C and even its keys can be considered as good as the original HP keys!
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 30 indicating that the unit is almost 30 times faster than the original HP-15C. As with the DM-15CC this is not consistent with my performance index measurements.
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: "DM15 M1B V16 48MHz"

Software Update There is a number of different firmware versions available on the rpn-calc / SwissMicros site.
For programming details see DM-41.
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, DM-15L, 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 20 loops specified in register 3 the program runs for 19.8 seconds.
The performance index calculates to 34 * 20 / 19.8 = 34.3

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