Rare findings season is opened!

[Diego Diaz]

Hi all,

Seems that a number of rare items are unexpectedly sowing up in the last few weeks.

First it was the STO. DOMINGO module:

Here.

Then the earliest (so far) pre-production HP-41C with its unique unreleased OS:

Here.

And now, the "Fish Population Dynamics" plug-in module for the HP-41CV:

Here... Just the manual, I'm affraid.

Does anyone has any info/knowlegde about this rarity? (Or have the real thing?)

More often someone come across a new rare module but, alas, no documentation. In this case the manual is available but the module isn't.

The range of applications for our beloved 41's is becoming wider and wider even though these ladies are about to reach the 40 yo mark. Awesome!

Best from Canary Islands.

Diego.

[Thomas Klemm]

(08-06-2018 11:48 PM)Diego Diaz Wrote:  And now, the "Fish Population Dynamics" plug-in module for the HP-41CV:

In Table 2 on page 4 we find a description of the:

Quote:Sequence of operations needed to load a program (FB n) from the FISHPOPDYN module into the memory of the HP 41CV calculator.

With a reference to a footnote:

Quote:Addressing the programs directly (as can be done, e.g. with the HP Stat Pac module) is not possible here, because the 15 programs on the FISHPOPDYN module have a number of local ALPHA labels in common.

I find that a bit weird. If I had the following structure in the module:

Code:

LBL "FB 1"
…
LBL A
…
END
LBL "FB 2"
…
LBL A
…
END
…

Couldn't I just GTO "FB 1" and then use A in USER mode to XEQ A within this 1st block?

And then GTO "FB 2" and use A to XEQ A in that 2nd block?

Am I missing something?

But then this description appears to be written by Corvallis Microtechnology Inc.

Cheers
Thomas

[Didier Lachieze]

(08-06-2018 11:48 PM)Diego Diaz Wrote:  And now, the "Fish Population Dynamics" plug-in module for the HP-41CV:

Here... Just the manual, I'm affraid.

Does anyone has any info/knowlegde about this rarity? (Or have the real thing?)

Good find !

This module seems to be a collection of 15 of the 30 programs published in this book.

So it should be possible to recreate it if there is any interest in this topic...

[Ángel Martin]

(08-07-2018 04:24 AM)Didier Lachieze Wrote:  Good find !

This module seems to be a collection of 15 of the 30 programs published in this book.

So it should be possible to recreate it if there is any interest in this topic...

Yes that seems to be the source book for the module. I could prepare a ROM file with the programs but I'd need a downloadable version of the document to work on, do you know if that's available?

ÁM

[Ángel Martin]

(08-06-2018 11:48 PM)Diego Diaz Wrote:  The range of applications for our beloved 41's is becoming wider and wider even though these ladies are about to reach the 40 yo mark. Awesome!

Indeed, and I'm very proud to have contributed to the breadth & depth with my own "extravagant" additions (not orthodox according to the prevailing winds ;-), such as the Spanish-English dictionary, the Country Capitals, and topping them all the Underground Maps (Metro Madrid, Paris Metro, Berlin U-Bahn, London Tube and NYC Subway - no less). Tons of fun!

[Dieter]

(08-07-2018 03:20 AM)Thomas Klemm Wrote:  With a reference to a footnote:

Quote:Addressing the programs directly (as can be done, e.g. with the HP Stat Pac module) is not possible here, because the 15 programs on the FISHPOPDYN module have a number of local ALPHA labels in common.

I find that a bit weird. If I had the following structure in the module:

Code:

LBL "FB 1"
…
LBL A
…
END
LBL "FB 2"
…
LBL A
…
END
…

Couldn't I just GTO "FB 1" and then use A in USER mode to XEQ A within this 1st block?

I can't say what made the author(s) of the manual or the module recommend such a weird prodecure. But, generally speaking, very often experts in a certain field (like fish breeding) are not experts in calculator programming and usage. There often is only a very limited understanding of how a device works and what are the preferred procedures and associated programming techniques. I remember several cases (some have been discussed here) where specialized HP41 software was far from being optimized, and some cases where even examples for bad programming style. This BTW also includes some of HP's own programs. But again: I can't say anything about this particular case, it's just what I recall from other similar cases.

According to point 4 in the mentioned table on page 4 all programs seem to get initizialied with [Shift] [c], i.e. a local alpha label. The usual and recommended way of doing such things would be another one: Each program should be started with [XEQ] FB 1, [XEQ] FB 2 ... etc. which sets the program pointer within that program and may also initialize other things (flags, data registers etc.). If local alpha labels are used also User mode should be set (SF 27). This is the common way such things are handled. But just like you I can't see why this has not been implemented in this particular case.

(08-07-2018 03:20 AM)Thomas Klemm Wrote:  But then this description appears to be written by Corvallis Microtechnology Inc.

They produced the module. But I don't think they proofread their customers' manuals and suggest changes.

Dieter

[Diego Diaz]

Hi all,

According to the book where the programs were taken from, these programs were intended to be distributed (sold?) as a pack of 142 magnetic cards.

This may explain the unusual procedure required to use the module as well as the interest in having (some of) these programs into a ROM PAc.

It was probably cheaper to provide the users with a module than purchasing a number of card readers and the correspondig sets of cards.

The module would more likely be an OTP version of the CMT-10 as the ones used in the BGUG & ML-IDC modules, hence the Corvallis Micro Technologies reference.

In this case the module was used in just as a program reservoir (used in a card-reader like fashion as peripheral "mass storage").

Re-coding the whole set of programs, so they can be run directly from the module, would have required a much longer effort and the chosen usage procedure seems to be a compromise to reduce cost and time to market.

Just a theory... of course.

Cheers

Diego.

PS. Someone by the Philippines area who can check if any such module shows up? :-P

[Thomas Klemm]

(08-07-2018 03:20 AM)Thomas Klemm Wrote:  Addressing the programs directly (as can be done, e.g. with the HP Stat Pac module) is not possible here, because the 15 programs on the FISHPOPDYN module have a number of local ALPHA labels in common.

(08-07-2018 04:24 AM)Didier Lachieze Wrote:  This module seems to be a collection of 15 of the 30 programs published in this book.

Meanwhile I had a look at some of the programs. The problem I see is that multiple of them use the same global ALPHA labels, e.g. LBL "P" which probably forced them to load only one program at the time. Otherwise a GTO "P" could possibly end up in another program.

Cheers
Thomas

[Ángel Martin]

(08-07-2018 11:27 AM)Thomas Klemm Wrote:  Meanwhile I had a look at some of the programs. The problem I see is that multiple of them use the same global ALPHA labels, e.g. LBL "P" which probably forced them to load only one program at the time. Otherwise a GTO "P" could possibly end up in another program.

That's not unusual with this type of collections, and it's easy enough to correct just by modifying the LBL's to make them different from each other...

[Thomas Klemm]

(08-07-2018 11:40 AM)Ángel Martin Wrote:  it's easy enough to correct just by modifying the LBL's to make them different from each other...

Or then make them local instead. That probably happened since labels A-J are local and then all of a sudden from "K" on they are global. Except when using synthetic programming of course.

Kind regards
Thomas

[rprosperi]

The intro in the book says that the 41 programs were 'adapted' from HP-67/97 programs, which explains the, um... non-optimal programming/label choices and operational procedures. Although now 41 programs, they are still operated the old way. Instead of "Load the cards" and then use A-E keys for program operation" they simply run the program name in lieu of "Load the cards".

I think this supports Diego's theory; it looks like they made minimal changes to the 67 programs to run on the 41, then likely had them burned in the OTP modules as an expedient. Had they taken the time to re-write the programs to leverage 41 features, they surely could have included several to many more of the original programs. If they had contracted CMT to port the programs, they surely would have made changes to global labels, etc.

Thanks for reporting this Diego, very interesting.

[Didier Lachieze]

(08-07-2018 01:26 PM)rprosperi Wrote:  The intro in the book says that the 41 programs were 'adapted' from HP-67/97 programs

For the fish counters who prefer the good old HP LED displays and don’t mind juggling with (lots of) magnetic cards here is the link to the original book with the HP67/97 program listings:

Fish Population Dynamics in Tropical Waters: a manual for use with programmable calculators.

[Thomas Klemm]

(08-07-2018 03:11 PM)Didier Lachieze Wrote:  For the fish counters who prefer the good old HP LED displays and don’t mind juggling with (lots of) magnetic cards here is the link to the original book with the HP67/97 program listings

Thanks for providing the link to the book. Not that I'm into counting fish but I still find it fascinating to see what has been done with the limited resources they had.

Kind regards
Thomas

[Monte Dalrymple]

(08-07-2018 03:11 PM)Didier Lachieze Wrote:  

(08-07-2018 01:26 PM)rprosperi Wrote:  The intro in the book says that the 41 programs were 'adapted' from HP-67/97 programs

For the fish counters who prefer the good old HP LED displays and don’t mind juggling with (lots of) magnetic cards here is the link to the original book with the HP67/97 program listings:

Fish Population Dynamics in Tropical Waters: a manual for use with programmable calculators.

I like the comment on page 4 of the book:

"do not blame the author for the nonsensical results that may result from thoughtless applications of the methods and programs given here."

Words to live by.

[John Keith]

(08-07-2018 04:37 PM)Monte Dalrymple Wrote:  I like the comment on page 4 of the book:

"do not blame the author for the nonsensical results that may result from thoughtless applications of the methods and programs given here."

Words to live by.

Or in other words, GIGO