Richard Nelson's pictures of the 4 HP 15c versions

[Gene Wright]

[Paulo MO]

A firmware updated 15c+ as a regular, permanent, stock item? That would be nice. But maybe we should call it 15c*, because you know what they say: "when you wish upon a star..." ( and I never heard the version "when you wish upon a plus...")

:-)

Paulo

Edited: 20 Feb 2012, 3:50 p.m.

[Richard J. Nelson]

All four machines shown use the same ROMs. Is it 15C or 15c? I once asked Sam Kim the general question regarding HP Calculator model numbers. The answer, he said, was that which is on the calculator, i.e. it is an HP-15C. The marketing types will want the "new" generation machine to be lower case C" but they are dealing with a legacy machine so they are "torn" between the old and the new. In the end I use whatever is printed on the calculator.

There is one exception, however. It is the model number used most often. Does anyone remember this model (hint: it is a "recent" small machine)?

X < > Y,

Richard

[Jan]

The marketing types will want the "new" generation machine to be lower case C" but they are dealing with a legacy machine so they are "torn" between the old and the new.

Marketing guys usually have no clue. If it had been up to them there would have been no HP-35 at all (and probably no HP-45, HP-55....). The capital C stands for 100 in roman numerals, which is about the relative increase in speed of the new 15C's compared to the old ones. For me it should therefore be a capital C (still) much like the V and X represented the the memory-increase (in roman numerals) of the 41CV and 41CX models compared to the 41C.

[Alexander Oestert]

What's a 15c+ again? Some prototype?

[Eric Smith]

Yes. A very limited number were made, and some were given out at a conference. The hardware is basically the same as the new 12C.

[robert rozee]

a question that has probably been asked before... does there exist a 15c+ with firmware such that:

- it does not exhibit the PSE bug

- the battery low indicator works

- it has no other major 'flaws'?

[Katie Wasserman]

I don't have a 15C+ but this question has come up here before, and I've been paying close attention. While there are older versions of the ARM-based 15C firmware none of them have the battery indicator working correctly nor are they otherwise bug-free.

The 12C+ also does not have the battery indication working.

OTOH, Jeff did some extensive battery testing on the 15C LE and found that battery life was much better than one would expect given the 20ma load, when he used very high quality cells. Still the low battery indicator did not work at all (?) when the cells were finally exhausted.

[Geoff Quickfall]

Unfortunately my 15c+ as with other beta testers was updated with each new version. As a result there may not be many with the original firmware.

I do remember there were only about 125 lines of program memory and many bugs in the original.

Also line number access was problematical to say the least.

Cheers, Geoff

[Alexander Oestert]

Could the experts elaborate on the question if it would be possible to port the DM-15CC's firmware to the HP 15C LE hardware as it seems to be bug free? Or the code that go15c for Android is based on which also has no apparent bugs.

[Paul Dale]

I'd start with an older version of Nonpareil and port that to the 15C LE.

- Pauli

[uhmgawa]

Quote:

---

Could the experts elaborate on the question if it would be possible to port the DM-15CC's firmware to the HP 15C LE hardware as it seems to be bug free? Or the code that go15c for Android is based on which also has no apparent bugs.

---

Several folks have asked for a KEMU port to the sam7 voyager.
KEMU sidesteps all of the known problems with the current sam7
15c le firmware and additionally supports full NUT/voyager
emulation including system/keypad self test, synthetic
programming via y^x rotate-22, command line interface, multiple
voyager family models, even the NUT ptr==13 CPU errata.
It is fairly configurable and currently is optimized for size:
bundled with a 15c firmware image it is
well under 32K on an AVR core SoC and I'd expect substantially
less for an ARM footprint. Even with all voyager images of
(11c/12c/15c/16c), graphic support, and assorted bells & whistles
as demonstrated in the
Graphic Voyager Prototype,
image size is under 64KB.
Requiring support for only the sam7 voyager's segment display,
image size reduces
further and usage would be essentially the same the
KINOMI/KEMU voyager. The point here being over half of the sam7's
128KB flash would be available for further optimization,
functional customization, or user persistent storage.

The hold up thus far has been over logistics rather than
technical issues, concerning how a prospective user deals
with obtaining voyager firmware. The images I've been using
have been captured from voyagers I own rather than elsewhere.
Ideally I'll be able to reach some understanding with HP to allow
bundling these images with a KEMU release but we're not there
yet. The alternative of finding images elsewhere is certainly
possible and that may be a fall-back if bundling isn't an
option. But it is unwelcome end user clunkiness best avoided.

[Ingo Paschke]

Quote:

---

The hold up thus far has been over logistics rather than
technical issues, concerning how a prospective user deals
with obtaining voyager firmware. The images I've been using
have been captured from voyagers I own rather than elsewhere.
Ideally I'll be able to reach some understanding with HP to allow
bundling these images with a KEMU release but we're not there
yet. The alternative of finding images elsewhere is certainly
possible and that may be a fall-back if bundling isn't an
option. But it is unwelcome end user clunkiness best avoided.

---

An alternative firmware would be really great, this could make the 15LE the ultimate version of the 15C.

Regarding clunkiness: It's already clunky enough to obtain the cable and flash the firmware with (my)samba, so the step of obtaining the 15C firmware and combining it with the emulator should be no real obstacle. If checksums and headers are all at the start of the file, couldn't it even be as simple as concatenating the two files?

[uhmgawa]

Quote:

---

An alternative firmware would be really great, this could make the 15LE the ultimate version of the 15C.

---

The ultimate version of a 15c starts with a board swap of
a 24xx <= S/N < 28xx 15c chassis with a suitable ARM core, reusing
the enclosure along with the superior key caps and segment LCD
found in the legacy voyager. The logical conclusion would be
somewhere in the ballpark of a matrix display and external
i/o + power.

Quote:

---

Regarding clunkiness: ... If checksums and headers are all at the start of the file, couldn't it even be as simple as concatenating the two files?

---

It certainly could be made as simple for the case of a single
15c voyager model firmware. However for the general case of
multiple images metadata is needed to describe each image to KEMU.
Unless some sort of additional tool was created to obviate
a rebuild, having a gcc toolchain available would be required.
The anticipated "clunkiness" was of dealing with this vs.
having prebuilt binary images available in a prospective
KEMU release.

[Ingo Paschke]

Quote:

---

It certainly could be made as simple for the case of a single
15c voyager model firmware.

---

While the ability to switch the firmware is really neat and impressive, it wouldn't be of much use (at least to me), because I wouldn't know how to use a 12c or even a 16c with the 15c's keycaps.

Edited: 24 Feb 2012, 4:19 a.m.

[Katie Wasserman]

Quote:

---

The images I've been using have been captured from voyagers I own rather than elsewhere. Ideally I'll be able to reach some understanding with HP to allow bundling these images with a KEMU release but we're not there yet.

---

In another recent thread the nonexistent copyright of this firmware was mentioned as it has been several times before. Given that, what is there to discuss with HP, just having some agreement that they won't bother you with frivolous lawsuits?

[uhmgawa]

Quote:

---

In another recent thread the nonexistent copyright of this firmware was mentioned as it has been several times before.

---

Nothing in that thread nor associated research constitutes
concrete legal advice -- at least not to my comfort level.

Quote:

---

Given that, what is there to discuss with HP, just having some agreement that they won't bother you with frivolous lawsuits?

---

Let it suffice to say my reading of the tea leaves suggests
HP isn't at all pleased with an external attempt to
commercialize their firmware and tread on their brand image.
Doing nothing may also be construed as abandonment of any
copyright/infringement claim, although I'll leave that for
greater legal minds to debate.
In any case I thought it reasonable to first see where such
an upfront discussion may lead before considering alternatives.

On perhaps a personal note, what I'd developed wouldn't have
existed if HP didn't release engineering specifications
for their NUT silicon. I'd prefer not to be a potential
source of regret for that decision.

[robert rozee]

how about someone produce the firmware image, complete, and release it anonymously into the wild to fly "like an eagle on the winds"? there might be no glory to be had, but there would be a great many very happy 15C LE owners out there!! call it 'doing a public good'...