HP-34C Integrate Memory Usage

[Chumango]

Unless I have missed it somewhere, the HP-34C manual does not mention the memory requirements to use integrate. Does it use dedicated memory space, or the memory space that is discussed elsewhere in the manual?

The HP-15C and the HP-41 advantage module manuals both give the memory requirements for integration. I don't see it in the HP 34C manual.

[rprosperi]

I believe I recall reading (somewhere... sometime... probably the HPJ article) that the 34C needs no 'free' user memory, it needs only the stack parameters and the user's program, which I guess that implies it uses only internal ACT registers. Contrasting with a Windows application comprised of 32MB code and needing another 30-50MB of RAM.

[brouhaha]

Unlike the later 15C, and the Advantage PAC for the 41, the 34C does have dedicated internal registers for solve and integrate, which are not otherwise available to the user. These registers do not participate in memory partitioning.

This was done because it is much more difficult to write Woodstock (or Nut) microcode that uses registers at arbitrary addresses, and doing that would run more slowly.

In the 15C and 41, they arranged for the memory partitioning to always allocate the solve and integrate registers at a fixed address, the lowest addresses of user memory, by moving everything else upward. That way they got the same speed during calculation, with a little overhead of moving memory around beforehand.

[Chumango]

Interesting. I also find it interesting that the 15C uses space more efficiently. The 15C requires five registers for solve and 23 for integrate, whereas the 41 uses 13 for solve and 32 for integrate.

[Gene]

From the journal article in V7N6P30-31:

[teenix]

(02-23-2024 02:36 PM)Chumango Wrote:  Unless I have missed it somewhere, the HP-34C manual does not mention the memory requirements to use integrate. Does it use dedicated memory space, or the memory space that is discussed elsewhere in the manual?

The HP-15C and the HP-41 advantage module manuals both give the memory requirements for integration. I don't see it in the HP 34C manual.

This is a listing of all the RAM registers used for the integration example from the user manual. (31 in all) Every register in the ACT is used except [f] (used for internal instruction like f -> a)

All the register addresses used above 30 are not user accessible.

Code:


0
16
18
23
24
25
26
30 << code was reading program step
32
38
39
40
41
42
43
44
46
47
48
49
50
51
55
56
57
58
59
60
61
62
63

cheers

Tony

[SlideRule]

Two publications with regard to the topic at hand:

a) Remarks on Some Modified Romberg Algorithms for Numerical Integration, Numerical Mathematics and Applications (google books), page 57

" SUMMARY. it is shown that the algorithm for numerical integration used in the pocket calculators HP-34C and HP-15C may be regarded as an element in a class of extrapolation algorithm derived from Romberg's classical algorithm by a nonlinear transformation. Some properties of this class are discussed. "


b) Problems and Methodologies in Mathematical Software Production, Lecture Notes in Computer Science 142, ISBN 0-38741603-6 Springer-Verlag New York, 1982, 276 pages

"                                             Preface
     In November, 1980 a week-long International Seminar on Problems and
Methodologies in Mathematical Software Production was held in Sorrento, Italy.
     The Seminar was organized and supported by the National Committee for the
Mathematical Sciences and the National Group for Mathematical Informatics,
both of which are part of Italy's National Council for Research.
Additional Sponsors for the seminar were University di Napoli, AICA, Informatica
Campania (Italsiel).
     The Seminar was intended for university and industrial researchers …
     Their presentations are collected in this book.
…
This paper is a survey of those concepts that are fundamental to the task
of implementing numerical algorithms. In the next section we define computational
software and describe its relation to algorithms and activities in numerical
analysis. In Section 3 we introduce important details of the hardware
environment in which computational software is written and used. In section 4
we define and discuss the concepts of reliability, robustness and transportability.
In the last section we show how all these things affect the design
of an algorithm and its implementation into software. Throughout the paper,
simple examples involving elementary functions and hand calculators illustrate
the ideas discussed. An additional example is presented in an Appendix …
…
     We motivate our concerns for the environment and for the design and imple-
mentation of algorithms by experimenting with some simple programs. Consider
the evaluation of the magnitude of a complex number …
By definition …
This definition corresponds to the theoretical method for determining Izl, and
suggests the obvious algorithm of squaring the components, summing them, and
extracting the square root. Suppose we implement that algorithm on a programmable
hand calculator, a TI 59, say, and run it …
…
     When we try the same experiment on an HP 34C calculator, we obtain … "
etc.

BEST!
SlideRule