Questions about storage formats

Discussion around the Swiss Micros DM42 calculator.
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amafan
Posts: 60
Joined: Tue Sep 29, 2020 11:40 pm

Questions about storage formats

Post by amafan »

After working with the DM42 for awhile now, I have some questions about the storage formats for the extended memory. As I understand it the DM42 firmware is capable of taking a keystroke entry program and converting it to be stored in the extended RAM area. I have tried this and it works so all is well there. Conversely, a program in the extended RAM can be converted into the working memory for execution. As I understand it, only programs in the working memory can be executed.

Additionally, the Encoder program From @grsbanks (Thank you, BTW) is available in the technical section which allows program development to be done on the PC and subsequently encoded to .RAW format and transferred to the DM42 for execution on the DM42 after loading into the working memory. I've studied the DM42 operation manual and posts in this forum to garner this data. Consequently, I have a couple of questions for the community at large.

1. Am I correct in my understanding of the programming workflow and memory organization of the DM42?

2. What exactly is the .RAW format? I don't understand how the keystroke programming is converted to this format by the Encoder software. Is it a binary representation of the alphanumeric keystroke symbols utilizing the FOCAL binary representation?

3. Is there going to be an application developed for the Encoder for offline development?

I am a electrical engineer by training so I have a working knowledge of engineering mathematics and structured language programming. My daughter is trying to teach me Python and I'm looking at RPL as I have recently acquired an HP48GX and HP28S. I wanted to have a high end HP calculator when I was a practicing engineer but they were out of my reach financially. The DM42 is like a dream come true.

Regards,
DM41X (#6476), 42 (#458) - HP 17BII, 35(2), 45, HP 27S, 28S, 30B, 41CV, 42S, 48S, 35S, HP10bII+, 12C PLAT
I may have a problem!
rprosperi
Posts: 1107
Joined: Mon Apr 24, 2017 7:48 pm
Location: New York

Re: Questions about storage formats

Post by rprosperi »

I'll give you some high-level replies here, I'm sure Godwin (grsbanks) will fill-in with more thorough comments.

Basically, yes you seem to understand the functional split between calculator memory (which the simulated 42S operates on) and what you call extended memory. The real 42S has no equivalent of this additional memory, but DM42 uses it for a variety of things including importing and exporting .raw files.

The .raw file format is a binary representation of the FOCAL byte code which Free42 operates on, as part of simulating a 42S. HP built the 42S essentially copying the HP-41 FOCAL byte code with some small extensions (why reinvent the wheel when the 41 wheel rolled so well?) and Thomas created Free42 to operate as closely as possible as how the real 42S would on the same code. I believe the .raw file format was created by Warren Furlow, when he wrote V41, but I could be mistaken.

Godwin can comment about a future offline encoder/decoder. An analogous tool has been announced for the DM41/DM41L, but I honesty don't know if that could be used here.

Is there a problem with using the online encode/decode tools, other than you need to be online to use it?

Learning RPL and Python simultaneously is bound to lead to some confusion, they could not be more different. It's hard to say if you'll enjoy RPL; some RPN fans learning RPL love and embrace it and never look back, due to it's truly superior power and flexibility, while others hate it and campaign vehemently against it, decrying its complexity, huge variety of types and write-only characteristics. Both are right; as I said, it's a matter of taste and personal preference.

Thanks for taking the time to study the manuals and explore the DM42 yourself prior to posting, to be able to ask good, informed questions.
--bob p

DM42: β00071 & 00282, DM41X: β00071 & 00656, DM10L: 071/100
nephilim
Posts: 23
Joined: Sat Sep 12, 2020 10:09 pm

Re: Questions about storage formats

Post by nephilim »

Regarding 3)

I am using Microsoft Visual Studio with the HP42S-free42 extension by J. Heilingbrunner to write programs on my Mac. I encode them within Visual Studio and test the raw-files in Free42 before storing them on the DM42.
amafan
Posts: 60
Joined: Tue Sep 29, 2020 11:40 pm

Re: Questions about storage formats

Post by amafan »

nephilim wrote:
Sat Feb 06, 2021 1:42 pm
Regarding 3)

I am using Microsoft Visual Studio with the HP42S-free42 extension by J. Heilingbrunner to write programs on my Mac. I encode them within Visual Studio and test the raw-files in Free42 before storing them on the DM42.
Can you give me a link to the extension for Visual Studio? Thank you in advance and for sharing your development environment.
DM41X (#6476), 42 (#458) - HP 17BII, 35(2), 45, HP 27S, 28S, 30B, 41CV, 42S, 48S, 35S, HP10bII+, 12C PLAT
I may have a problem!
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