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Re: [DM15L] Got mine

Posted: Sat Jan 13, 2018 10:25 am
by Michael
Krauts In Space wrote:
Sat Jan 13, 2018 10:00 am
What about the foam pads, glued to the PCB? Up to 70°C might make them shrink an vanish away ;) Or should I not mind about them?
Yes, the foam might shrink a little, don't worry too much about it.
Krauts In Space wrote:
Sat Jan 13, 2018 10:00 am
Annunciators: I did as rprosperi recommended but it's still a pain in the ass. Pressing the f or g key succesively should disable the annunciator.
I also would like to have that 'nulling' of a keypress like at the HP41, when a key is held down for a second.
This is how the HP15C works, get over it.

Re: [DM15L] Got mine

Posted: Sat Jan 13, 2018 2:56 pm
by rprosperi
Krauts In Space wrote:
Sat Jan 13, 2018 10:00 am
Annunciators: I did as rprosperi recommended but it's still a pain in the ass. Pressing the f or g key succesively should disable the annunciator.

I also would like to have that 'nulling' of a keypress like at the HP41, when a key is held down for a second.
These are both cases where the DM15L behaves exactly the same as the original HP-15C, because it is actually running the original 15C firmware; behaving exactly the same as the original is one of the most basic goals of the SM machines.

Most users of these machines have been users of the original versions for many years, so not likely to be problems (or even noticed) by them. And although I can certainly understand how you might see these changes as added convenience, the work by SM to learn, modify and test the original code to implement these does not seem justified, at least to me, however other DM15 users could agree.

Re: [DM15L] Got mine

Posted: Sun Jan 14, 2018 10:45 am
by Krauts In Space
rprosperi wrote:
Sat Jan 13, 2018 2:56 pm
Krauts In Space wrote:
Sat Jan 13, 2018 10:00 am
Annunciators: I did as rprosperi recommended but it's still a pain in the ass. Pressing the f or g key succesively should disable the annunciator.

I also would like to have that 'nulling' of a keypress like at the HP41, when a key is held down for a second.
These are both cases where the DM15L behaves exactly the same as the original HP-15C, because it is actually running the original 15C firmware; behaving exactly the same as the original is one of the most basic goals of the SM machines.

Most users of these machines have been users of the original versions for many years, so not likely to be problems (or even noticed) by them. And although I can certainly understand how you might see these changes as added convenience, the work by SM to learn, modify and test the original code to implement these does not seem justified, at least to me, however other DM15 users could agree.
Hi Bob,
I can understand this view.
I simply thought that such things would improve usability without altering functionality.
And with a look to the DM42: folks are happy for the new 6 buttons that allow entering text and menu without reserving the upper function keys row.
Also the new text input like with the HP41C and HP48GX that I own comes to my mind.
The DM42 has a far more reaching change in usability than my proposal.
Real time clock, more memory and what else more? (Can't have a look on my toy, it's currently in the oven :) )

Re: [DM15L] Got mine

Posted: Sun Jan 14, 2018 10:49 am
by keithdalby
The DM42 and DM15 are different projects with different aims, as far as I can tell. The DM15L is a clone of the HP15c using an emulator. The DM42 uses the the Free42 simulator at its core, but does not seek to emulate nor simulate the HP42s except insomuch that it has broad compatibility with HP42s programs.

Of course, I could completely have the wrong end of the metaphorical stick.

Re: [DM15L] Got mine

Posted: Sun Jan 14, 2018 12:04 pm
by grsbanks
The aim for both is to have something that behaves as closely as possible to the original. What differs between the DM1x/41 series and the DM42 is precisely how that is achieved on a technical level.

There is no copyright on the ROM of the HP Voyager and 41C series. It is therefore possible to write an emulator for the underlying Nut processor and run the original ROM within that emulator. This is precisely what the LPC1115 based SwissMicros machines do.

This changed for Free42 and, by extension, for the DM42. There *is* a prominent copyright notice in the ROM of the HP-42S. Using that ROM in another product, commercial or otherwise, is therefore a strict no-no and is one of the reasons, If I understand correctly, why Thomas Okken wrote Free42 as a completely new application simulating the operation of the HP-42S rather than an emulator using a ROM image.

What this means is, the suggested alterations to the way the DM15 works mean actually rewriting the HP-15C's ROM image, and without any formal documentation of it, eg. a full listing, that means reverse-engineering the whole thing. A larger company might well have the resources to do this if they were willing to commit to the expense (none have TTBOMK). SwissMicros is just Michael and David working flat out on the DM42. This isn't going to happen any time soon :)

Re: [DM15L] Got mine

Posted: Mon Apr 16, 2018 11:30 am
by Zaphod
Got my DM15L today , very nice ...

Only I ordered a DM41L :? :roll: :cry:

also , by the by.... I just thought I'd add it seems to exhibit the same thing with the rubber feet in the first post, the screws fly very close to the table surface :o

Re: [DM15L] Got mine

Posted: Mon Apr 16, 2018 1:41 pm
by Zaphod
Zaphod wrote:
Mon Apr 16, 2018 11:30 am
Got my DM15L today , very nice ...

Only I ordered a DM41L :? :roll: :cry:
Problem sorted quickly by Michael , and luckily as I was going to buy a 15L eventually it's all worked out I guess, I just get them in a different order :D