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Full Version: What has the DM41 extra over the HP42s?
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Let me begin to admit that I never owned or used a HP41. From what I have read here, the 41 could do 1 thing all its successors could not: interface with external hardware via some kind of (serial?) port.

This is exactly the function the DM41X has not. It can send its output to a printer but that's it.

So I am curious if there is anything I don't know about that the DM41X can do that the DM42 can't. The programming model should be nearly identical, and I see that Thomas is already porting specific 41 functions to Free42 so I expect those to become available with a firmware update for the DM42 somewhere in the future.
The existing software base that runs on the 41X is enormous. 500+ rom modules full of every type of software you can imagine will run on it. . . much of that in mcode.

The software base of the 42 is much smaller. . . sure, it includes a number of things built-in already, but that's the basic difference in my opinion.



And... I really like both the 41 and the 42, so not trying to be snob here!
(10-26-2020 12:03 AM)Gene Wrote: [ -> ]The existing software base that runs on the 41X is enormous. 500+ rom modules full of every type of software you can imagine will run on it. . . much of that in mcode.
And that will not run on a 42? And can those modules not be installed on a DM41(L), considering that the DM41X costs almost twice as much?

The 41X has of course advantages over the 41(L), like a better screen and more management options like the DM42. It is portrait instead of landscape, but I won't enter that holy war again.

Quote:And... I really like both the 41 and the 42, so not trying to be snob here!
I do have a DM42, but I'm just wondering if getting a DM41X is interesting for me or not.

I realize this subject has the potential to evolve in a holy war, that was definitely not my intention.
Free42 has most of the functions of the 41CX, the exceptions being the functions that deal with extended memory, the stop watch, and alarms. (CLRGX, GETKEYX, and the six indirect comparison functions X=NN? etc. are also missing but will be added in the next release.)

This means that Free42, and hence the DM42, will run most HP-41 user code software. That includes user code ROMs, which can be converted to raw files using the rom2raw program and imported.

What Free42, and hence the DM42, can not run is anything that involves HP-41 machine code, or that requires extended memory. That's a fundamental limitation. Running HP-41 machine code requires HP-41 hardware, or something that emulates HP-41 hardware accurately, and that is not something Free42 was designed to do.
Answering that depends on what you typically do with calculators and what you plan to do and enjoy doing.

If you mostly write your own programs, and your interests lie in math calculations and engineering kids of applications, then I'd say the DM42/Free42 is the better choice. The DM42 has far better precision, is much faster, supports matrices and complex types natively and has some enhanced features for easily adding menus, etc. into your programs.

On the other hand if you prefer to explore other pre-written software, and/or are interested in dabbling with extending or modifying the environment (just to see if you can) then the 41X is probably a better choice. On the 41X you can use FOCAL (41/42 user code) but also Synthetic programming, which is artificial combinations of original commands, extended to do things unplanned by HP (somewhat akin to what the original hackers were doing in the 70s/80s) and also machine/assembler code.

The 41X ecosystem provides modules and other tools to accomplish most of the things the 42 can do (complex, matrices, etc.) but they are less trouble, more consistent and integrated better in the DM42, so you may as well use those if that's the goal.

hth
(10-25-2020 11:44 PM)johanw Wrote: [ -> ]Let me begin to admit that I never owned or used a HP41.

One of the most important points: The 41 was a groundbreaking classic, the 42 is only tech.

41 years ago, the HP41 was the first alphanumeric mobile computer and started the age we consider normal today.

The most important point between the HP41C(V/X) am the HP42S was external storage. There was no way to save the programs of an HP42 on external memory. After a reset or a new purchase, all programs had to be re-entered via the keyboard. Therefore, the HP42s was never a real alternative for HP41 users.

The charm of a classic, the incomparable font, the buttons for + - * / on the left side in addition to the higher compatibility are reasons for a DM41X instead of a DM41L or DM42.
(10-26-2020 12:16 AM)johanw Wrote: [ -> ]And that will not run on a 42? And can those modules not be installed on a DM41(L), considering that the DM41X costs almost twice as much?

Correct. The modules won't run on a DM42 or a DM41L
(10-26-2020 06:49 AM)Peet Wrote: [ -> ]The most important point between the HP41C(V/X) am the HP42S was external storage. There was no way to save the programs of an HP42 on external memory. After a reset or a new purchase, all programs had to be re-entered via the keyboard. Therefore, the HP42s was never a real alternative for HP41 users.

While a key difference as Peet says, this is not the case with the DM42, you can easily copy programs (or a complete machine state file) to/from the DM42 via USB to the FAT drive on the DM42. This really key difference between the original platforms has been removed on the DM42.


(10-26-2020 06:49 AM)Peet Wrote: [ -> ]The charm of a classic, the incomparable font, the buttons for + - * / on the left side in addition to the higher compatibility are reasons for a DM41X instead of a DM41L or DM42.

As you never owned a 41C, these likely sound like minor considerations, but for folks that owned and used 41s since the 80's, these are important considerations that can dwarf more 'important' ones. Calcaholism is an odd thing...
(10-26-2020 06:49 AM)Peet Wrote: [ -> ]One of the most important points: The 41 was a groundbreaking classic, the 42 is only tech.

That matters when you're curating a museum, not when you're trying to pick the best tool for the job.

(10-26-2020 06:49 AM)Peet Wrote: [ -> ]The charm of a classic, the incomparable font, the buttons for + - * / on the left side in addition to the higher compatibility are reasons for a DM41X instead of a DM41L or DM42.

In other words, taste? I bought my first HP-41C the week it came out and I enjoyed using it very much, but the fact that anyone can get hung up on which side the arithmetic keys are on will never cease to amaze me. I switch back and forth between the two all the time and the number of typos this causes is approximately zero. Big Grin

I'll grant that the HP-42S display contrast is poor but then again I find the HP-41C display font ugly. With modern hardware you can get a nice bit-mapped display and good contrast at the same time.
(10-26-2020 12:41 PM)rprosperi Wrote: [ -> ]This really key difference between the original platforms has been removed on the DM42.

If HP did this 30 years ago, the HP42s maybe had the chance to be the successor of the 41. But then they brought the HP48 instead. Wink

(10-26-2020 02:30 PM)Thomas Okken Wrote: [ -> ]That matters when you're curating a museum, not when you're trying to pick the best tool for the job.

Using over 30 or 40 years old tech is mostly more retro/hobby than best tool.
(10-26-2020 03:20 PM)Peet Wrote: [ -> ]Using over 30 or 40 years old tech is mostly more retro/hobby than best tool.

Speak for yourself! I didn't write Free42 out of nostalgia and I'm pretty sure most of its users actually use it, just like I do myself...
I have both the DM 41X and the DM42 and I like them both.

Yes, there is a portion of nostalgia in using both of them, perhaps somewhat more in using DM41X. I think this is OK but it is likewise OK to ask for a practical comparison.

If it comes to practical usability I think there are basically two aspects which make the trade off:
- In favor of the DM 41X is the huge amount of software written for the HP41 that is readily available and that can be used on the DM41X without any adoption (as long as the HP-IL module is not used).
- In favor of the DM42 is speed (about 26 times faster), accuracy (number of digits more than three times) and overall the more modern concept. Programs written for the HP41 mostly do not need much change to run on DM42 as long as no module software is used but if a module function (e.g. integration) is used there is some work to do in order to adopt it.

There is one additional aspect which concerns older DM 42 compared to new DM41X (and new DM42). This is the keyboard that is much better with the new caculators. So if you want the new keyboard and you already have an older DM42 this might be a reason to buy a new DM41X.

Best

Raimund
(10-26-2020 03:50 PM)Thomas Okken Wrote: [ -> ]I didn't write Free42 out of nostalgia and I'm pretty sure most of its users actually use it, just like I do myself...

Even if you say so, I doubt it. A lot of nostalgia is probably an important reason for your excellent piece of work.
(10-26-2020 03:20 PM)Peet Wrote: [ -> ]Using over 30 or 40 years old tech is mostly more retro/hobby than best tool.

True for the most part, however I find the HP-41 to be one piece of old tech that has aged really well.

I do a lot of numeric base work, bit fiddling, really low level debug work and find the abilities to do this on a calculator like the HP-41 or HP-16C to be better than anything else I ever tried.

Also often overlooked with the HP-41 (the 42 should share this too) is the really low barrier of writing a short program to do some specialized task. You start with a simple repetitive calculation and realize that it is better to write a program (macro) to do it once and for all. Then you bind it to a key and have it easy available. It becomes part of your customized tool. Add on top of this that it never misses a key press and it is easy to get things right (once you learned the basics). And yes, instant on, fits into your pocket and runs for weeks on a set of batteries.

There will not be a new model coming next year that replaces it. You can get software updates despite its age. There is no built in life cycle which will make it nearly impossible to use in 5-10 years. My HP-41 calculators have been used for 35-40 years now.
(10-26-2020 05:01 PM)Peet Wrote: [ -> ]
(10-26-2020 03:50 PM)Thomas Okken Wrote: [ -> ]I didn't write Free42 out of nostalgia and I'm pretty sure most of its users actually use it, just like I do myself...

Even if you say so, I doubt it. A lot of nostalgia is probably an important reason for your excellent piece of work.

Thanks for the compliment, but what is it you doubt, exactly? Are you so sure your attitude is the only valid one that everyone who has a different take must be misremembering their own experience? 2004 wasn't that long ago and I'm not senile yet, I remember pretty well what motivated me back then.

I was looking for a scientific programmable calculator app to run on my Palm PDA, and I didn't like the ones that were available. So I decided to write my own. As I was working on the design, I noticed that I was copying aspects of the HP-42S UI rather often, so after I while I decided to just copy the 42S completely rather than reinvent the wheel. It's a good design and it doesn't stop being so just because it's old.
I've only been seriously using the 42S and DM42 since around 2017, and it's typically my go-to calculator when I'm not doing work that's better served by a more application-specific model (e.g. financial calculator, programmer's calculator). So it's certainly not nostalgia in my case.

I also have a 41CX and DM41X, which are terrific machines, but the 42 will have undeniably broader appeal to someone not entrenched in the 41 ecosystem (or who just likes tinkering with old computer equipment).
(10-26-2020 03:20 PM)Peet Wrote: [ -> ]If HP did this 30 years ago, the HP42s maybe had the chance to be the successor of the 41. But then they brought the HP48 instead. Wink

Keep in mind the HP-42S was introduced as the successor of the HP-15C, and not the HP-41C. The original vision for what eventually became the 42S included I/O and it was going to be the 41C successor, but when that was yanked (debates ensue to this day as to why, I personally think it was to not impact 28C/S sales) HP knew that they had to re-position it, and ended up aiming a great deal lower.
(10-26-2020 06:52 PM)Thomas Okken Wrote: [ -> ]Are you so sure your attitude is the only valid one that everyone who has a different take must be misremembering their own experience?

In 2020 both a 32 and a 41 year old pocket calculator are equally nostalgic and good tools for their job. Technically the HP42s may be the winner in many and the Free42/DM42 in nearly all asspects, but historically the HP41 has a higher weight. Therefore, I mention the historical aspects as advantages of the DM41X over the 42.

P.S. I realy think your Free42 is one of the best RPN Apps/Programs. After my disappointment with the app go41cx I use free42 to run my old HP41-Prgs. The Attachmend is how your App looks on my Phones Wink
(10-26-2020 05:01 PM)Peet Wrote: [ -> ]
(10-26-2020 03:50 PM)Thomas Okken Wrote: [ -> ]I didn't write Free42 out of nostalgia and I'm pretty sure most of its users actually use it, just like I do myself...

Even if you say so, I doubt it. A lot of nostalgia is probably an important reason for your excellent piece of work.

Sorry to burst your bubble but I fully concur with Thomas. Free42 can be and actually is used nowadays (2020) profitably, even for professional work, as I've done myself in the past and continue doing in the present.

It's unbelievably fast, has unbelievable accuracy, runs in most current OSs in all devices from a tiny Palm Z22 to a huge desktop PC, and it's eminently usable and convenient: you can get your manual calculations performed in seconds and your programs written out and running in minutes, then get results in milliseconds or less, thanks to RPN and Thomas' awesome implementation.

With a few additional functionalities added it has the potential to become the very best math-oriented portable virtual calculator ever, bar none, RPN or otherwise.

If you doubt it, well, your loss.

V.
(10-26-2020 10:47 PM)Valentin Albillo Wrote: [ -> ]Sorry to burst your bubble but I fully concur with Thomas. Free42 can ...
If you doubt it, well, your loss.

Thomas commented my statement to the HP41 vs. HP42s (not Free42).
I however think in 2020 both a 32 and a 41 year old pocket calculator are equally nostalgic and good tools for their job.

The DM(Free)42 wins in Tech, the DM41x with his Retro-Charme.
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