Speed comparison Swissmicros / HP

[Bernd Grubert]

I have used the Bessel function of first kind to carry out a benchmark for some models of SwissMicros and HP. The program is taken from the book "HP-41 Extended Functions Made Easy" by Keith Jarett, Synthetix, 1983.
It can run on the HP-41C and the HP-15C with nearly the same code. The only modifications necessary is the conversion of the register and label numbers from one to two digits. The program for the 15C-calculator is listed at the bottom of the message. I calculated J(50,50.0). The calculator returned 0.1214090222 (result from Wolfram Alpha: 0.1214090218976...)

Here are the execution times:

Code:

calculator  |  execution time  |  remarks
------------+------------------+-----------
HP-41CV     |        87.6 sec  |
HP-41CL     |        85.1 sec  |  TURBOX
HP-41CL     |         4.9 sec  |  TURBO50
DM-41L      |       115.7 sec  |  12 MHz
DM-41L      |        73.7 sec  |  48 MHz
DM-41L*     |        43.9 sec  |  12 MHz
DM-41L*     |        10.7 sec  |  48 MHz
HP-15CLE    |         2.1 sec  |
DM-15L      |        51.7 sec  |  12 MHz
DM-15L      |        12.6 sec  |  48 MHz
HP-15C      |       258.9 sec  |

The times for the -41s were measured with the internal clock. The times for the -15s were taken manually and are therefore less accurate (+/-0.1 sec).
The DM-41L* data refer to an DM-41L with DM-15 firmware.
What wonders me is that the DM-41L is so much slower than the DM-15L. It's also strange, that the speed increase for the DM-41L from 12 MHz to 48 MHz is only 1.6x instead of 4x for the DM-15L.
May be there is some potential for optimisation in the DM-41L.

Here is the code I used:

Code:

# --------------------------------------------
# HEWLETT·PACKARD 15C Simulator program
# Created with version 3.4.00
# --------------------------------------------
#T:JNX
#D:Program calculates Jn(x)
Store order n in Y and x in X.
Program taken from the book "HP-41 Extended Functions Made Easy" 
by Keith Jarett, Synthetix, 1983
#L-2:Bessel Function of first kind and order n
#R0:order n
#R1:Jn(x)
#R2:Norm
#R3:x
#R4:Ji(x)
#R5:Ji+1(x)
#R6:Jn+1(x)
#R7:2i
# --------------------------------------------
   000 {             } 
   001 {    42 21 12 } f LBL B
   002 {       44  3 } STO 3
   003 {       43 16 } g ABS
   004 {           5 } 5
   005 {          40 } +
   006 {          34 } x↔y
   007 {       44  0 } STO 0
   008 {    43 30  8 } g TEST x<y
   009 {          34 } x↔y
   010 {       43 44 } g INT
   011 {           4 } 4
   012 {          20 } ×
   013 {       44  7 } STO 7
   014 {          15 } 1/x
   015 {       44  2 } STO 2
   016 {       44  4 } STO 4
   017 {       44  5 } STO 5
   018 {    42 21  0 } f LBL 0
   019 {       45  5 } RCL 5
   020 {          16 } CHS
   021 {       45  7 } RCL 7
   022 {       45  3 } RCL 3
   023 {          10 } ÷
   024 {       45  4 } RCL 4
   025 {       44  5 } STO 5
   026 {          20 } ×
   027 {          40 } +
   028 {       44  4 } STO 4
   029 {       45  7 } RCL 7
   030 {           4 } 4
   031 {          10 } ÷
   032 {       42 44 } f FRAC
   033 {    43 30  0 } g TEST x≠0
   034 {          10 } ÷
   035 {    44 40  2 } STO + 2
   036 {       45  0 } RCL 0
   037 {           2 } 2
   038 {    44 30  7 } STO − 7
   039 {          20 } ×
   040 {       45  7 } RCL 7
   041 {    43 30  6 } g TEST x≠y
   042 {       22  1 } GTO 1
   043 {       45  4 } RCL 4
   044 {       44  1 } STO 1
   045 {       45  5 } RCL 5
   046 {       44  6 } STO 6
   047 {       45  7 } RCL 7
   048 {    42 21  1 } f LBL 1
   049 {    43 30  0 } g TEST x≠0
   050 {       22  0 } GTO 0
   051 {       45  4 } RCL 4
   052 {    44 30  2 } STO − 2
   053 {       45  2 } RCL 2
   054 {    44 10  1 } STO ÷ 1
   055 {    44 10  4 } STO ÷ 4
   056 {    44 10  5 } STO ÷ 5
   057 {    44 10  6 } STO ÷ 6
   058 {       45  5 } RCL 5
   059 {       45  4 } RCL 4
   060 {       45  6 } RCL 6
   061 {       45  1 } RCL 1
   062 {       43 32 } g RTN
# --------------------------------------------

EDIT:
Updated the table with the data of the HP-15C and the converted DM-41L